research papers
A variable-temperature study of a
in barbituric acid dihydrateaSchool of Natural Sciences – Chemistry, Bedson Building, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, England
*Correspondence e-mail: w.clegg@ncl.ac.uk
The 4H4N2O3·2H2O) has twice been reported as orthorhombic, Pnma, with all atoms (except for CH2 H atoms) lying on the mirror plane [Al-Karaghouli et al. (1977). Acta Cryst. B33, 1655–1660; Jeffrey et al. (1961). Acta Cryst. 14, 881–887]. The present study has found that at low temperatures, below 200 K, the is no longer orthorhombic but is non-merohedrally twinned monoclinic, P21/n. This phase is stable down to 100 K. Above 220 K the is orthorhombic, and between 200 and 220 K the structure undergoes a phase change, with the monoclinic-to-orthorhombic itself taking place at around 216–217 K. The size of the β angle in the monoclinic structure is temperature dependent; at 100 K β is around 94° and it decreases in magnitude towards 90° as the temperature increases. Although the hydrogen-bonding motifs are the same for both crystal systems, there are significant differences in the crystal packing, in particular the out-of-plane displacement of the two water molecules and the sp3-hybridized C atom of barbituric acid.
of barbituric acid dihydrate (C1. Introduction
Over the past few years, the topic of phase transitions has become more and more popular for scientific investigation. This extremely broad field is actively pursued by physicists, chemists, materials scientists, earth scientists and metallurgists (Pandey, 2005). Indeed, the January 2005 edition of Acta Crystallographica Section A: Foundations of Crystallography was devoted almost entirely to the topic. A simple search in February 2005 of SciFinder Scholar 2004 (American Chemical Society, 2004) for `phase transition' resulted in almost 138 500 hits; the top five years according to the greatest numbers of hits were 2003, 2002, 2001, 2000 and 2004. The number of hits in 2003 is 9013, more than double that of 1995 (4457) and a clear indication of the increasing interest in the subject.
Our interest in the temperature-induced ; Cleverley & Williams, 1959; Craven et al., 1969, 1982; Craven & Vizzini, 1969, 1971; McMullan et al., 1978; Nichol & Clegg, 2005a,b; Platteau et al., 2005; Sambyal et al., 1995; Williams, 1973, 1974). Contemporary research continues to focus on barbituric acid as a model system for developing computational polymorph prediction techniques, something that is of major importance to the pharmaceutical industry (Lewis et al., 2004, 2005).
of barbituric acid dihydrate arose from our research on metal complexes of this and related ligands. Barbituric acid is the parent molecule of the barbiturate family of drugs, which are of crystallographic interest not least for their propensity to form polymorphs. The 5,5-dialkyl derivatives are those which are pharmacologically active and which have been most extensively characterized by X-ray crystallography (Caillet & Claverie, 19801.1. Analysis of current literature
The structure of barbituric acid dihydrate (I) appears twice in the primary literature: an X-ray diffraction study (Jeffrey et al., 1961) and a neutron diffraction study (Al-Karaghouli et al., 1977). In both reports the data collections were carried out at room temperature, and the and are reported as orthorhombic, Pnma. The final R factors are 0.14 and 0.087, respectively. Both reports conclude that, with the exception of the two H atoms of the CH2 group, all atoms of the barbituric acid and water molecules lie on the mirror plane. During their discussions, both reports make mention of the high atomic displacement observed in the b-axis direction (i.e. perpendicular to the mirror plane). Al-Karaghouli et al. (1977) considered the possibility of an alternative non-centrosymmetric Pn21a (non-standard setting of Pna21), which would allow the atoms to deviate from the (now non-crystallographic) mirror plane. These authors also considered a model in which one of the O atoms was deliberately displaced off the mirror plane and then refined as disordered. Neither of these models gave a satisfactory outcome and they concluded that there was no good reason to doubt the assignment of Pnma as the space group.
2. Experimental
2.1. Preliminary experiments
With these uncertainties in mind, we carried out a low-temperature redetermination of barbituric acid dihydrate for the purpose of having a reference structure of the ligand for reliable comparison with the structures of our metal complexes, also determined routinely at low temperature. It was found that, at 150 K, the P21/n. Curious to know whether this result pointed to inaccuracies in the literature reports (which were at least 27 years old), we re-collected data, from the same crystal, at room temperature. As reported by Jeffrey et al. (1961), the crystal decomposed on the diffractometer during data collection from a transparent colourless crystal to a white opaque solid, which did not diffract at all. Nevertheless, sufficient data were collected to confirm that at room temperature the structure is indeed orthorhombic with the Pnma. Hence the crystal had undergone a on warming from low temperature to room temperature (and, presumably, in the reverse direction in the initial flash-cooling). A variable-temperature X-ray diffraction study was carried out to observe the effect of changing temperature on the and to determine at what point the occurs.
was not orthorhombic but non-merohedrally twinned monoclinic and the was2.2. Sample preparation
Crystals of barbituric acid dihydrate were prepared by dissolving a sample of commercially available barbituric acid (obtained as a white powder from Lancaster Synthesis) in distilled water with gentle heating. Storage at 278 K over a weekend resulted in large colourless and perfectly transparent block crystals of barbituric acid dihydrate.
2.3. Experimental strategy
Data were collected on a Bruker SMART 1K CCD diffractometer fitted with an Oxford Cryosystems Cryostream cooler (Cosier & Glazer, 1986) at 14 different temperatures ranging from 100 to 270 K. Experimental details for selected temperatures are summarized in Table 1 (details for all experiments are available in the deposited supplementary material1). A large good-quality crystal, which did not require cutting, was selected from the sample and, on the basis of preliminary experiments, the experimental strategy was started by re-collecting data at 150 K and then proceeding in the following temperature order: 170, 190, 200, 210, 220, 230, 215, 217, 218, 219, 216, 100 and 270 K. A full data collection, as opposed to a simple unit-cell determination, was carried out at each temperature. Such a procedure adds several days to the time taken to conduct the experiments; however, it also allows for complete structure solution and – the ultimate indicator of correctness and data quality – at each temperature and is especially important when one considers that the crystals were twinned in the monoclinic a full data collection allows the determination of unit-cell parameters for both components of the twin from several hundred reflections, rather than the hundred or so that would be measured by only collecting partial data for an orientation matrix. The same data collection strategy (complete sphere of 0.3° width frames, 30 s exposures) was used for each experiment.
The reasons for selecting two extreme temperatures to finish the strategy were to check that the crystal did not undergo a second , was used for every experiment; the crystal was not removed from the goniometer head between data collections, and a visual examination of the crystal at the end of the experiments showed that it suffered no physical effects (e.g. cracking) as a result of the cooling and heating. Ultimately the same crystal stayed attached to the goniometer head for over 2 weeks.
at even lower temperatures; so we could verify that the is reversible; so that we could see that the crystal did not suffer physical stress at extreme cold; and so we could collect data as close to room temperature as possible without the crystal decomposing. The same crystal, pictured in Fig. 1The true crystal temperature was verified by collecting data on a crystal of CsOH·H2O (purchased from Lancaster Synthesis). Caesium hydroxide monohydrate is known to undergo a from C-centred monoclinic to hexagonal at 229 K (Tomaszewski, 1992). This was observed at 228–229 K and so the crystal temperature as reported by the Cryostream was found to be reliable. After each temperature change the crystal of barbituric acid dihydrate was allowed to stabilize at the new temperature for around 30 min before starting the data collection.
2.4. Data processing
For each collection the data were processed both as monoclinic and as orthorhombic, regardless of the symmetry implied by the data. This approach proved especially important for those data sets collected around the transition temperature. For example, those data sets which were clearly monoclinic were also processed as orthorhombic, with the β angle constrained in cell after integration and the set as Pmnb. We chose this unconventional setting of Pnma so that the unit-cell axes matched those of the monoclinic P21/n, thus allowing for detailed comparison of the two structures. Similarly the orthorhombic data sets were integrated as monoclinic with no constraints on the β angle and the P21/n selected. By treating each data set in this way and comparing the final monoclinic and orthorhombic results it was, in most cases, obvious which was correct and which was incorrect.
Starting with the 150 K collection the programs GEMINI and SMART (Bruker, 2001) were used to determine and refine both components of the twin. SAINT (Bruker, 2001) was then used to integrate the data and TWINABS (Sheldrick, 2002) was used to correct for absorption and other effects and to write two corrected data files for structure solution and The SHELXTL suite of programs was used for determination, structure solution and (Sheldrick, 2001). Having refined the structure as non-merohedrally twinned monoclinic to a satisfactory conclusion the data processing was repeated as described above with orthorhombic constraints. We used SADABS (Sheldrick, 2003) and not TWINABS for absorption correction of the (untwinned) orthorhombic data sets. Molecular diagrams and other graphics were produced using DIAMOND (Brandenburg & Putz, 2004) and MERCURY (Version 1.3; Bruno et al., 2002).
This approach was followed for all other data collections, and the non-H atomic coordinates from the 150 K collection were used as starting parameters for structure Pmnb to constrain the atoms to lie on the mirror plane in accordance with the space-group symmetry. Anomalies in some of the ranges are discussed below.
at all other temperatures. This procedure ensured that factors such as unit-cell origin, atomic coordinates and atomic labels were consistent throughout. Appropriate adjustments were made to the coordinates of the structures in3. Results and discussion
A summary of the . Examination of the results at each temperature shows that it is possible to classify each one as definitely monoclinic, definitely orthorhombic or `transitional', where it is not immediately obvious which is the most appropriate and in some cases both crystal systems seem appropriate. The ADDSYM function of PLATON (Spek, 2003) was very useful in the detection of additional symmetry in the monoclinic structures.
results for each data collection is presented as Table 2
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3.1. Diffraction patterns
Examination of the diffraction pattern is the most reliable way of determining the correct shows three screenshots of a frame recorded at 100, 215 and 230 K with the crystal in the same orientation. On each frame two pairs of reflections have been highlighted. They share common h and k indices but differ in the value of l (as indicated on the 230 K frame). One reflection of each pair belongs to one component of the twin and the other reflection belongs to the second component of the twin. The two components are related by a 180° rotation about the c axis. At 100 K, a monoclinic temperature, the reflections are well separated and the program GEMINI could easily index both twin components. As the temperature increases the reflections begin to move closer together and at 215 K, a transitional temperature, they are starting to merge. Indexing the diffraction pattern is now not so easy, and both monoclinic and orthorhombic unit cells can be determined. At 230 K pairs of reflections have merged completely, to give discrete reflections with unique indices, and the structure is now orthorhombic.
of a structure. As a simple example, Fig. 23.2. Unit-cell parameters
Table 3 gives unit-cell parameters for all experiments. Phase transitions are often accompanied by a significant change in unit-cell dimensions, such as the doubling of an axis. Here there is little change in the size of the save for a gradual increase in unit-cell volume so that the at 270 K is around 19 Å3 larger than that at 100 K. This difference is largely insignificant, given that unit cells measured at or near room temperature are generally larger than those measured at low temperatures.
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3.3. Orthorhombic structures
Data collected at 220, 230 and 270 K are classed as definitely orthorhombic. At these temperatures GEMINI was unable to determine two separate twin components from the diffraction patterns so the possibility that the data were non-merohedrally twinned was discarded. Orthorhombic and pseudo-orthorhombic models both gave similar satisfactory values of R when had converged, so we examined the pseudo-orthorhombic models for additional symmetry. The use of ROTAX (Cooper et al., 2002) showed that 180° rotations were possible about the [100], [010] and [001] reciprocal and directions, and analysis with ADDSYM showed an additional mirror plane missing from the model. It was simple to conclude that, at these temperatures, the structures are indeed, as has twice been reported, best described in the higher-symmetry Pmnb (or Pnma) rather than in P21/n.
Taking the structure at 230 K as an example, a displacement ellipsoid plot and a packing diagram viewed along the c axis of (I) are given in Fig. 3. H atoms were all located in a difference map and refined with Uiso = 1.2Ueq(C,N,O); their coordinates were refined freely. All atoms, with the exception of the CH2 H atoms, lie on the mirror plane (one of the H atoms in the ellipsoid plot is symmetry generated); this fact is neatly shown by the packing diagram. The two water molecules are coplanar with the barbituric acid ring. Molecular dimensions are unexceptional and in agreement with those reported by Al-Karaghouli et al. (1977), with the exception of the X—H bonds, which are around 0.1–0.2 Å shorter than the previously reported values. This difference is to be expected, since ours is an X-ray diffraction study and we are comparing it with neutron diffraction results.
3.4. Monoclinic structures
Those structures determined at 100, 150, 170 and 190 K are classed as definitely monoclinic with P21/n. In each case the diffraction pattern is non-merohedrally twinned. That the diffraction pattern is twinned as a result of the orthorhombic-to-monoclinic transition is not surprising and is quite common in situations of a material changing from higher to lower symmetry. The two components of the twin are related by a 180° rotation about the c axis, and at low temperatures the extent of the is such that one can clearly see the reflections from both components in the diffraction pattern, as shown in Fig. 2. Attempts to refine these data with orthorhombic models result in refinements with very large R factors. Another curious feature is the change in the magnitude of the β angle with temperature; as shown in Table 3, the β angle approaches 90° as the temperature increases towards the All of these structures share another common feature in that the barbituric acid molecule is no longer planar. In this there is no imposed mirror symmetry and as a result the Csp3 (C4) atom, with its tetrahedral rather than trigonal geometry, is seen to deviate from the mean plane of the rest of the molecule.
Fig. 4 shows a displacement ellipsoid plot of (I) at 100 K. All H atoms were identified in a difference and their coordinates were refined, with the exception of the CH2 H atoms, which were positioned geometrically (C—H = 0.99 Å) and constrained as riding during All H atoms were refined with Uiso = 1.2Ueq(O,N,C). Molecular dimensions, listed in Table 4, are unexceptional and, with the exception of the torsion angles, are more or less the same as those determined at 230 K. Fig. 5 shows an overlay of the monoclinic structure at 100 K (red) and the orthorhombic structure at 230 K (black), produced by plotting the mean plane (r.m.s. deviation 0.0288 Å) of atoms C1, O1, N1, C2, O2, C2, N2, C3 and O3 of the monoclinic 100 K structure against the planar ring of the orthorhombic 230 K structure. The out-of-plane displacement of the C4 atom can be clearly seen. This is not an unprecedented observation; the structure of unsolvated barbituric acid shows a similar puckering in the ring (Bolton, 1963; Lewis et al., 2004). By using the CALCALL function of PLATON we determined the Cremer–Pople ring puckering parameter Q at 100 K to be 0.0787 Å. This is a very small value but does indicate that at 100 K the ring is distorted to a measurable degree in the At higher temperatures the ring puckering is less significant and CALCALL does not report it. This small, but significant, conformational flexibility of the barbituric acid molecule has proved to be a major obstacle in polymorph prediction (Lewis et al., 2004).
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In addition to the ring puckering, the two water molecules are no longer coplanar with the barbituric acid ring. This is a more significant change from the orthorhombic structure and, as a consequence, the molecular packing shows some obvious differences. Fig. 6 shows a packing diagram of the structure at 100 K, viewed along the c axis. The hydrogen-bonding motifs in both the orthorhombic and the monoclinic structures are identical but here, because the water molecules are no longer coplanar with the barbituric acid molecules, some adjustment in the packing is necessary to preserve the hydrogen-bonding arrangement. Thus, instead of observing perfectly planar sheets of hydrogen-bonded water and barbituric acid molecules, we see sheets that are now rippled in appearance. Hydrogen-bonding parameters are given in Table 5.
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3.5. Transitional structures
The structures refined from data collected between 200 and 219 K are classed as `transitional'; that is to say, aspects of the data and the gives details of the final outcomes for both space groups and shows also the unconstrained β angle as determined in the monoclinic models. At these temperatures the choice of monoclinic versus orthorhombic was not immediately obvious, and several different approaches to each data set were tried in order to determine which cell setting and best described the data.
imply that the structure is undergoing change of some sort. Table 6
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As can be seen from the and 6, data quality at these temperatures was much poorer than those at lower or higher temperatures. In particular, the data above 2θ = 50° were much weaker than previously observed, and removal of these data from the led to a marked improvement in the quality of R and wR. High-angle data quality usually depends on factors such as crystal size and quality, scattering power of the atoms, disorder within the structure, and temperature of data collection. In this study the same crystal was used throughout and the structure is rigid with little scope for disorder, leaving just the effect of increasing temperature as a possible cause of weaker high-angle data. It is true that the lower the crystal temperature, the higher the diffracted X-ray intensities are, and so the more distinguishable from the background are the reflections. However, this fact would not account for such a marked decrease in the data quality from 190 to 200 K. Usually in such a case one would be justified in omitting these poor data from the least-squares calculations. However, this approach would not be appropriate in this case. That the high-angle data at transitional temperatures are poor in comparison to other collections is a significant observation in this study, and it is for this reason that the resolution of the and structure reporting were not restricted to 2θmax = 50°.
results presented in Tables 2Another significant observation is the difference between the minimum and maximum transmission factors resulting from the TWINABS/SADABS scaling, as presented in Table 1. The differences between Tmin and Tmax at 100, 230 and 270 K are reasonable; however, those reported at 200, 215 and 217 K are not. TWINABS and SADABS correct for absorption by comparing the intensities of supposedly equivalent (by symmetry) or repeated (as a result of collecting redundant data) reflections. Given that the same crystal was used for all experiments, the large range of transmission at these intermediate temperatures cannot be connected to the shape or size of the crystal. Each data set was collected using an identical strategy, ruling out the possibility of variation due to changes in experimental settings. The wide variations in the putative absorption corrections must be a partial compensation for the poor quality of data from an intermediate structural state by the frame-scaling procedure in these multi-scan correction methods. We do not believe the variations are due to any hysteresis effect of structural change lagging behind temperature change, since the is not a large one, and the crystal was held at each new temperature for at least 30 min before data collection began. However, it should be noted that the temperature interval between these data sets is of the same order as the uncertainty in the temperature itself. If the is one that takes place gradually over a range of several degrees in temperature then some minor variation in the structure, and hence in the diffraction pattern, during each data collection is likely. These intermediate structures should each be regarded as an average structure over a small temperature range, and the range of transmission factors probably reflects this, together with the generally poorer results compared with those at higher and lower temperatures where a single phase is present.
3.5.1. Structures at 200, 210, 215 and 216 K
After much experimentation, several unit-cell determinations, the creation of many different models and seemingly endless ADDSYM was used to detect missed symmetry and in each case none was detected. The data collected at 215 and 216 K are of particular interest. Examination of the diffraction pattern at 215 K showed pairs of reflections and, although the separation of the reflections was quite small, they are an indicator of However, at 216 K there are virtually no pairs of reflections; instead they are seen merged and take the form of smeared ellipses rather than separate discrete isotropic spots. of the orthorhombic model gave a similar result to that of the monoclinic model, and it is possible that there was a combination of both monoclinic and orthorhombic unit cells coexisting in equilibrium at the same time.
cycles, it was concluded that, at these temperatures, the crystal structures are better described as monoclinic rather than orthorhombic. However, in each case the decision was very close and, if taken based on alone, would have been difficult to determine. To verify that orthorhombic was not a more appropriate description of the data,3.5.2. Structures at 217, 218 and 219 K
At these temperatures the balance begins to tip towards the orthorhombic GEMINI was able to determine two orientation matrices, of the structure was poor, giving very high values of R and wR (0.133 and 0.278, respectively). The refined twin fraction had a very high uncertainty, thus making the parameter (and therefore the twinning) meaningless. As a result the non-merohedrally twinned monoclinic model was quickly discarded. A pure (i.e. untwinned) monoclinic model was tried, giving a slightly better result; however, both ADDSYM and ROTAX suggested that this model was no longer appropriate. Although the unconstrained β angle is still almost a degree away from 90°, at 217 K the orthorhombic model gives the most satisfactory result and we can say that the orthorhombic model is, on balance, the better way to describe the data. At 218 and 219 K the results for the orthorhombic system become increasingly more favourable, and we now are more-or-less able to disregard the monoclinic as a reliable way of describing the structure; rather than being merely `better described' as orthorhombic they are now clearly orthorhombic – a subtle but important difference.
The first major observation at 217 K is that the non-merohedrally twinned is no longer an appropriate model for the data. Although4. Conclusions
The two previously reported crystal structures of barbituric acid dihydrate in Pnma only hold true at temperatures above 220 K. Below 200 K the is better described as non-merohedrally twinned monoclinic in P21/n, and between 200 and 220 K the undergoes a from monoclinic to orthorhombic. The is not particularly sharp; whilst the point at which the majority of the diffraction pattern changes from monoclinic to orthorhombic is probably around 216–217 K, the full transition appears to take place over a rather wider temperature range. The transition is reversible and the crystal suffers no physical effects as a result of either the temperatures used or the transition itself.
In the monoclinic structure the magnitude of the β angle is seen to vary with temperature. The angle approaches 90° as the temperature approaches the There are no other significant changes in unit-cell dimensions and the observed increase in unit-cell volume is insignificant.
The structural differences in changing from the orthorhombic to monoclinic phase are most clearly seen by looking at the displacement of the Csp3 atom of the barbituric acid ring and the significant movement of the two water molecules away from coplanarity with the barbituric acid, as presented in Fig. 5. The orthorhombic phase features all atoms (with the exception of the CH2 H atoms) lying on the mirror plane imposed by the although in the monoclinic phase this is no longer a symmetry requirement and the molecules have the freedom to distort and shift. The hydrogen-bonding motif of both the orthorhombic and monoclinic phases is the same; however, the physical arrangement of the molecules is different, and this difference is best seen by viewing and comparing c-axis projections of the orthorhombic and monoclinic phases.
Supporting information
10.1107/S0108768105017258/ws5026sup1.cif
contains datablocks 100, 150, 170, 190, 200, 210, 215, 216, 217, 218, 219, 220, 230, 270. DOI:Structure factors: contains datablock 100. DOI: 10.1107/S0108768105017258/ws5026100sup2.hkl
Structure factors: contains datablock refine. DOI: 10.1107/S0108768105017258/ws5026150sup3.hkl
Structure factors: contains datablock twin. DOI: 10.1107/S0108768105017258/ws5026170sup4.hkl
Structure factors: contains datablock refine. DOI: 10.1107/S0108768105017258/ws5026190sup5.hkl
Structure factors: contains datablock twin. DOI: 10.1107/S0108768105017258/ws5026200sup6.hkl
Structure factors: contains datablock twin. DOI: 10.1107/S0108768105017258/ws5026210sup7.hkl
Structure factors: contains datablock twin. DOI: 10.1107/S0108768105017258/ws5026215sup8.hkl
Structure factors: contains datablock twin. DOI: 10.1107/S0108768105017258/ws5026216sup9.hkl
Structure factors: contains datablock 217. DOI: 10.1107/S0108768105017258/ws5026217sup10.hkl
Structure factors: contains datablock 218. DOI: 10.1107/S0108768105017258/ws5026218sup11.hkl
Structure factors: contains datablock 219. DOI: 10.1107/S0108768105017258/ws5026219sup12.hkl
Structure factors: contains datablock 220. DOI: 10.1107/S0108768105017258/ws5026220sup13.hkl
Structure factors: contains datablock 230. DOI: 10.1107/S0108768105017258/ws5026230sup14.hkl
Structure factors: contains datablock 270. DOI: 10.1107/S0108768105017258/ws5026270sup15.hkl
For all compounds, data collection: Bruker SMART; cell
Bruker SAINT; data reduction: Bruker SAINT. Program(s) used to solve structure: using coordinates of another structure for 100, 190, 200, 210, 215, 216, 217, 218, 220, 230; Bruker SHELXTL for 150; SHELXS97 (Sheldrick, 1990) for 170; by using coordinates of another structure for 219; using coordinates of 150K structure for 270. Program(s) used to refine structure: Bruker SHELXTL for 100, 150, 190, 200, 210, 215, 216, 217, 218, 219, 220, 230, 270; SHELXL97 (Sheldrick, 1997) for 170. For all compounds, molecular graphics: Bruker SHELXTL; software used to prepare material for publication: Bruker SHELXTL and local programs.C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.591 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 3196 reflections |
a = 6.0970 (5) Å | θ = 2.3–28.3° |
b = 12.7152 (10) Å | µ = 0.15 mm−1 |
c = 8.8587 (7) Å | T = 100 K |
β = 94.0510 (14)° | Block, colourless |
V = 685.05 (9) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2263 independent reflections |
Radiation source: sealed tube | 2126 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.019 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; (Sheldrick, 2002) | h = −7→7 |
Tmin = 0.861, Tmax = 0.978 | k = −16→16 |
9480 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.032 | Hydrogen site location: mixed |
wR(F2) = 0.085 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.11 | w = 1/[σ2(Fo2) + (0.0407P)2 + 0.142P] where P = (Fo2 + 2Fc2)/3 |
2263 reflections | (Δ/σ)max = 0.009 |
120 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.30 e Å−3 |
C4H4N2O3·2H2O | V = 685.05 (9) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.0970 (5) Å | µ = 0.15 mm−1 |
b = 12.7152 (10) Å | T = 100 K |
c = 8.8587 (7) Å | 0.53 × 0.42 × 0.15 mm |
β = 94.0510 (14)° |
Bruker SMART 1K CCD diffractometer | 2263 independent reflections |
Absorption correction: multi-scan TWINABS; (Sheldrick, 2002) | 2126 reflections with I > 2σ(I) |
Tmin = 0.861, Tmax = 0.978 | Rint = 0.019 |
9480 measured reflections |
R[F2 > 2σ(F2)] = 0.032 | 0 restraints |
wR(F2) = 0.085 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.11 | Δρmax = 0.32 e Å−3 |
2263 reflections | Δρmin = −0.30 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.24519 (15) | 0.55163 (6) | 0.47580 (8) | 0.01876 (19) | |
O2 | 0.23088 (14) | 0.44143 (6) | 0.95897 (8) | 0.01791 (19) | |
O3 | 0.30272 (16) | 0.79018 (6) | 0.88813 (9) | 0.0201 (2) | |
O4 | 0.22481 (16) | 0.88638 (6) | 0.23924 (9) | 0.0205 (2) | |
H1O | 0.243 (3) | 0.9158 (13) | 0.3213 (18) | 0.025* | |
H2O | 0.236 (3) | 0.9297 (13) | 0.1714 (18) | 0.025* | |
O5 | 0.28797 (17) | 0.67316 (7) | 0.21840 (9) | 0.0219 (2) | |
H3O | 0.258 (3) | 0.7355 (15) | 0.2292 (17) | 0.026* | |
H4O | 0.269 (3) | 0.6452 (13) | 0.3010 (19) | 0.026* | |
N1 | 0.23187 (17) | 0.49826 (7) | 0.71716 (9) | 0.0134 (2) | |
H1N | 0.225 (2) | 0.4367 (12) | 0.6887 (15) | 0.016* | |
N2 | 0.25606 (16) | 0.61721 (7) | 0.92041 (10) | 0.01297 (19) | |
H2N | 0.259 (2) | 0.6290 (12) | 1.0177 (17) | 0.016* | |
C1 | 0.24285 (17) | 0.57458 (8) | 0.60971 (11) | 0.0126 (2) | |
C2 | 0.23845 (18) | 0.51492 (8) | 0.87146 (11) | 0.0122 (2) | |
C3 | 0.27180 (18) | 0.70381 (8) | 0.83037 (12) | 0.0132 (2) | |
C4 | 0.24598 (19) | 0.68713 (8) | 0.66181 (11) | 0.0131 (2) | |
H4A | 0.1073 | 0.7210 | 0.6225 | 0.016* | |
H4B | 0.3681 | 0.7237 | 0.6157 | 0.016* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0319 (5) | 0.0137 (4) | 0.0107 (4) | 0.0011 (3) | 0.0018 (3) | −0.0003 (3) |
O2 | 0.0302 (5) | 0.0112 (4) | 0.0124 (4) | −0.0004 (3) | 0.0017 (3) | 0.0021 (3) |
O3 | 0.0357 (5) | 0.0098 (4) | 0.0142 (4) | −0.0016 (3) | −0.0022 (3) | −0.0009 (3) |
O4 | 0.0363 (5) | 0.0133 (4) | 0.0117 (4) | −0.0020 (4) | 0.0014 (3) | −0.0006 (3) |
O5 | 0.0416 (5) | 0.0137 (4) | 0.0109 (4) | 0.0002 (4) | 0.0055 (4) | 0.0005 (3) |
N1 | 0.0213 (5) | 0.0075 (4) | 0.0114 (4) | −0.0002 (3) | 0.0006 (3) | −0.0009 (3) |
N2 | 0.0201 (5) | 0.0099 (4) | 0.0090 (4) | 0.0002 (3) | 0.0015 (3) | −0.0008 (3) |
C1 | 0.0143 (5) | 0.0114 (5) | 0.0120 (5) | 0.0009 (4) | 0.0005 (4) | 0.0003 (3) |
C2 | 0.0140 (5) | 0.0110 (5) | 0.0116 (4) | −0.0001 (4) | 0.0007 (4) | −0.0005 (3) |
C3 | 0.0158 (5) | 0.0104 (4) | 0.0134 (5) | 0.0014 (4) | 0.0003 (4) | 0.0006 (3) |
C4 | 0.0198 (5) | 0.0087 (4) | 0.0106 (5) | 0.0000 (4) | 0.0002 (4) | 0.0018 (3) |
O1—C1 | 1.2227 (13) | N1—C2 | 1.3810 (13) |
O2—C2 | 1.2172 (13) | N2—H2N | 0.874 (15) |
O3—C3 | 1.2205 (13) | N2—C2 | 1.3728 (13) |
O4—H1O | 0.819 (17) | N2—C3 | 1.3670 (13) |
O4—H2O | 0.822 (17) | C1—C4 | 1.5034 (14) |
O5—H3O | 0.821 (18) | C3—C4 | 1.5054 (14) |
O5—H4O | 0.828 (17) | C4—H4A | 0.9900 |
N1—H1N | 0.823 (15) | C4—H4B | 0.9900 |
N1—C1 | 1.3643 (13) | ||
H1O—O4—H2O | 109.3 (16) | O2—C2—N2 | 122.13 (9) |
H3O—O5—H4O | 105.4 (15) | N1—C2—N2 | 117.01 (9) |
H1N—N1—C1 | 117.9 (9) | O3—C3—N2 | 119.69 (10) |
H1N—N1—C2 | 116.5 (9) | O3—C3—C4 | 123.01 (9) |
C1—N1—C2 | 125.59 (9) | N2—C3—C4 | 117.29 (9) |
H2N—N2—C2 | 118.0 (10) | C1—C4—C3 | 115.90 (8) |
H2N—N2—C3 | 116.1 (10) | C1—C4—H4A | 108.3 |
C2—N2—C3 | 125.87 (9) | C1—C4—H4B | 108.3 |
O1—C1—N1 | 120.77 (9) | C3—C4—H4A | 108.3 |
O1—C1—C4 | 121.62 (9) | C3—C4—H4B | 108.3 |
N1—C1—C4 | 117.59 (9) | H4A—C4—H4B | 107.4 |
O2—C2—N1 | 120.85 (9) | ||
C2—N1—C1—O1 | 176.84 (11) | C2—N2—C3—O3 | −174.70 (11) |
C2—N1—C1—C4 | −4.70 (16) | C2—N2—C3—C4 | 6.22 (17) |
C3—N2—C2—O2 | 178.03 (11) | O1—C1—C4—C3 | −172.47 (10) |
C3—N2—C2—N1 | −1.30 (17) | N1—C1—C4—C3 | 9.09 (15) |
C1—N1—C2—O2 | −178.88 (10) | O3—C3—C4—C1 | 171.19 (11) |
C1—N1—C2—N2 | 0.47 (17) | N2—C3—C4—C1 | −9.76 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.819 (17) | 1.969 (17) | 2.7583 (11) | 161.9 (16) |
O4—H2O···O1ii | 0.822 (17) | 2.034 (17) | 2.8508 (11) | 172.4 (15) |
O5—H3O···O4 | 0.821 (18) | 1.931 (19) | 2.7463 (12) | 171.7 (17) |
O5—H4O···O1 | 0.828 (17) | 1.967 (18) | 2.7819 (12) | 167.9 (16) |
N1—H1N···O3iii | 0.823 (15) | 1.986 (16) | 2.8084 (12) | 177.2 (14) |
N2—H2N···O5iv | 0.874 (15) | 1.861 (15) | 2.7277 (12) | 171.2 (14) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.586 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 4632 reflections |
a = 6.1130 (8) Å | θ = 2.3–28.2° |
b = 12.7149 (16) Å | µ = 0.15 mm−1 |
c = 8.8564 (11) Å | T = 150 K |
β = 93.437 (2)° | Block, colourless |
V = 687.14 (15) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2212 independent reflections |
Radiation source: sealed tube | 2148 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −7→7 |
Tmin = 0.861, Tmax = 0.978 | k = −16→16 |
8078 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.051 | Hydrogen site location: mixed |
wR(F2) = 0.132 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.26 | w = 1/[σ2(Fo2) + (0.0334P)2 + 0.5782P] where P = (Fo2 + 2Fc2)/3 |
2212 reflections | (Δ/σ)max = 0.009 |
120 parameters | Δρmax = 0.38 e Å−3 |
0 restraints | Δρmin = −0.34 e Å−3 |
C4H4N2O3·2H2O | V = 687.14 (15) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1130 (8) Å | µ = 0.15 mm−1 |
b = 12.7149 (16) Å | T = 150 K |
c = 8.8564 (11) Å | 0.53 × 0.42 × 0.15 mm |
β = 93.437 (2)° |
Bruker SMART 1K CCD diffractometer | 2212 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 2148 reflections with I > 2σ(I) |
Tmin = 0.861, Tmax = 0.978 | Rint = 0.029 |
8078 measured reflections |
R[F2 > 2σ(F2)] = 0.051 | 0 restraints |
wR(F2) = 0.132 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.26 | Δρmax = 0.38 e Å−3 |
2212 reflections | Δρmin = −0.34 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2458 (3) | 0.55201 (11) | 0.47617 (15) | 0.0247 (4) | |
O2 | 0.2348 (3) | 0.44163 (11) | 0.95867 (15) | 0.0236 (4) | |
O3 | 0.2937 (3) | 0.79015 (11) | 0.88781 (17) | 0.0285 (4) | |
O4 | 0.2305 (4) | 0.88662 (12) | 0.23946 (18) | 0.0278 (4) | |
H1O | 0.250 (5) | 0.916 (2) | 0.320 (3) | 0.033* | |
H2O | 0.238 (5) | 0.929 (2) | 0.170 (3) | 0.033* | |
O5 | 0.2812 (4) | 0.67297 (13) | 0.21710 (18) | 0.0310 (4) | |
H3O | 0.256 (6) | 0.733 (3) | 0.227 (3) | 0.037* | |
H4O | 0.266 (5) | 0.648 (2) | 0.300 (4) | 0.037* | |
N1 | 0.2353 (3) | 0.49880 (13) | 0.71740 (18) | 0.0167 (4) | |
H1N | 0.234 (5) | 0.437 (2) | 0.690 (3) | 0.020* | |
N2 | 0.2549 (3) | 0.61716 (12) | 0.92001 (18) | 0.0161 (4) | |
H2N | 0.260 (5) | 0.6291 (19) | 1.014 (3) | 0.019* | |
C1 | 0.2440 (4) | 0.57482 (15) | 0.6094 (2) | 0.0157 (4) | |
C2 | 0.2408 (4) | 0.51528 (14) | 0.8709 (2) | 0.0157 (4) | |
C3 | 0.2682 (4) | 0.70428 (15) | 0.8303 (2) | 0.0167 (4) | |
C4 | 0.2468 (4) | 0.68739 (14) | 0.6622 (2) | 0.0166 (4) | |
H4A | 0.3700 | 0.7238 | 0.6167 | 0.020* | |
H4B | 0.1097 | 0.7215 | 0.6223 | 0.020* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0445 (11) | 0.0176 (7) | 0.0121 (6) | 0.0012 (8) | 0.0034 (7) | −0.0008 (5) |
O2 | 0.0422 (10) | 0.0136 (7) | 0.0151 (7) | 0.0007 (7) | 0.0020 (7) | 0.0032 (5) |
O3 | 0.0556 (12) | 0.0113 (7) | 0.0181 (7) | −0.0019 (8) | −0.0027 (8) | −0.0009 (5) |
O4 | 0.0529 (12) | 0.0151 (7) | 0.0153 (7) | −0.0038 (8) | 0.0023 (8) | −0.0017 (6) |
O5 | 0.0626 (13) | 0.0177 (7) | 0.0133 (7) | 0.0002 (9) | 0.0072 (8) | 0.0008 (6) |
N1 | 0.0279 (10) | 0.0066 (7) | 0.0156 (8) | 0.0008 (7) | −0.0001 (7) | −0.0007 (6) |
N2 | 0.0265 (10) | 0.0122 (7) | 0.0097 (7) | 0.0006 (7) | 0.0018 (7) | −0.0015 (6) |
C1 | 0.0199 (11) | 0.0123 (8) | 0.0151 (9) | 0.0022 (8) | 0.0019 (8) | 0.0006 (7) |
C2 | 0.0202 (11) | 0.0121 (8) | 0.0147 (9) | 0.0012 (8) | 0.0005 (8) | −0.0010 (7) |
C3 | 0.0208 (12) | 0.0113 (8) | 0.0179 (9) | 0.0006 (8) | −0.0001 (8) | 0.0009 (7) |
C4 | 0.0272 (12) | 0.0091 (8) | 0.0133 (9) | −0.0003 (8) | −0.0004 (8) | 0.0021 (6) |
O1—C1 | 1.216 (2) | N1—C2 | 1.374 (2) |
O2—C2 | 1.219 (2) | N2—H2N | 0.85 (3) |
O3—C3 | 1.211 (2) | N2—C2 | 1.367 (2) |
O4—H1O | 0.81 (3) | N2—C3 | 1.369 (2) |
O4—H2O | 0.83 (3) | C1—C4 | 1.505 (3) |
O5—H3O | 0.79 (3) | C3—C4 | 1.502 (3) |
O5—H4O | 0.81 (3) | C4—H4A | 0.9900 |
N1—H1N | 0.82 (3) | C4—H4B | 0.9900 |
N1—C1 | 1.363 (2) | ||
H1O—O4—H2O | 110 (3) | O2—C2—N2 | 121.94 (18) |
H3O—O5—H4O | 105 (3) | N1—C2—N2 | 117.15 (17) |
H1N—N1—C1 | 117.9 (17) | O3—C3—N2 | 119.74 (18) |
H1N—N1—C2 | 116.1 (17) | O3—C3—C4 | 123.18 (17) |
C1—N1—C2 | 125.91 (16) | N2—C3—C4 | 117.07 (16) |
H2N—N2—C2 | 118.7 (17) | C1—C4—C3 | 116.25 (15) |
H2N—N2—C3 | 115.3 (17) | C1—C4—H4A | 108.2 |
C2—N2—C3 | 125.94 (17) | C1—C4—H4B | 108.2 |
O1—C1—N1 | 120.98 (17) | C3—C4—H4A | 108.2 |
O1—C1—C4 | 121.84 (17) | C3—C4—H4B | 108.2 |
N1—C1—C4 | 117.17 (16) | H4A—C4—H4B | 107.4 |
O2—C2—N1 | 120.91 (17) | ||
C2—N1—C1—O1 | 177.4 (2) | C2—N2—C3—O3 | −175.4 (2) |
C2—N1—C1—C4 | −3.8 (3) | C2—N2—C3—C4 | 5.4 (4) |
C3—N2—C2—O2 | 178.2 (2) | O3—C3—C4—C1 | 172.7 (2) |
C3—N2—C2—N1 | −1.3 (4) | N2—C3—C4—C1 | −8.2 (3) |
C1—N1—C2—O2 | −179.1 (2) | O1—C1—C4—C3 | −173.7 (2) |
C1—N1—C2—N2 | 0.5 (4) | N1—C1—C4—C3 | 7.4 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.81 (3) | 1.98 (3) | 2.759 (2) | 161 (3) |
O4—H2O···O1ii | 0.83 (3) | 2.03 (3) | 2.850 (2) | 171 (3) |
O5—H3O···O4 | 0.79 (3) | 1.96 (3) | 2.743 (2) | 173 (4) |
O5—H4O···O1 | 0.81 (3) | 1.99 (3) | 2.781 (2) | 165 (3) |
N1—H1N···O3iii | 0.82 (3) | 2.00 (3) | 2.814 (2) | 175 (3) |
N2—H2N···O5iv | 0.85 (3) | 1.88 (3) | 2.721 (2) | 173 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.580 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 5619 reflections |
a = 6.1270 (5) Å | θ = 2.3–28.3° |
b = 12.7253 (11) Å | µ = 0.15 mm−1 |
c = 8.8633 (8) Å | T = 170 K |
β = 93.0680 (16)° | Block, colourless |
V = 690.06 (10) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2124 independent reflections |
Radiation source: fine-focus sealed tube | 2011 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
thin–slice ω scans | θmax = 28.4°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −8→8 |
Tmin = 0.823, Tmax = 0.978 | k = −16→16 |
9428 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.105 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.16 | w = 1/[σ2(Fo2) + (0.0469P)2 + 0.1845P] where P = (Fo2 + 2Fc2)/3 |
2124 reflections | (Δ/σ)max = 0.001 |
120 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.33 e Å−3 |
C4H4N2O3·2H2O | V = 690.06 (10) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1270 (5) Å | µ = 0.15 mm−1 |
b = 12.7253 (11) Å | T = 170 K |
c = 8.8633 (8) Å | 0.53 × 0.42 × 0.15 mm |
β = 93.0680 (16)° |
Bruker SMART 1K CCD diffractometer | 2124 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 2011 reflections with I > 2σ(I) |
Tmin = 0.823, Tmax = 0.978 | Rint = 0.024 |
9428 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.105 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.16 | Δρmax = 0.30 e Å−3 |
2124 reflections | Δρmin = −0.33 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2463 (2) | 0.55219 (7) | 0.47617 (10) | 0.0294 (3) | |
O2 | 0.2370 (2) | 0.44173 (7) | 0.95858 (10) | 0.0278 (3) | |
O3 | 0.2884 (2) | 0.79034 (7) | 0.88770 (11) | 0.0345 (3) | |
O4 | 0.2331 (2) | 0.88653 (8) | 0.23976 (12) | 0.0328 (3) | |
H1O | 0.245 (3) | 0.9170 (16) | 0.322 (2) | 0.039* | |
H2O | 0.241 (4) | 0.9287 (16) | 0.171 (2) | 0.039* | |
O5 | 0.2775 (3) | 0.67297 (9) | 0.21689 (11) | 0.0368 (3) | |
H3O | 0.257 (4) | 0.7371 (19) | 0.227 (2) | 0.044* | |
H4O | 0.259 (4) | 0.6454 (17) | 0.299 (2) | 0.044* | |
N1 | 0.2376 (2) | 0.49868 (8) | 0.71735 (11) | 0.0202 (2) | |
H1N | 0.232 (3) | 0.4357 (14) | 0.6897 (18) | 0.024* | |
N2 | 0.2547 (2) | 0.61732 (8) | 0.91989 (11) | 0.0192 (2) | |
H2N | 0.257 (3) | 0.6293 (13) | 1.015 (2) | 0.023* | |
C1 | 0.2447 (2) | 0.57488 (9) | 0.60978 (13) | 0.0190 (3) | |
C2 | 0.2423 (2) | 0.51518 (9) | 0.87116 (14) | 0.0188 (3) | |
C3 | 0.2661 (2) | 0.70408 (9) | 0.83007 (14) | 0.0203 (3) | |
C4 | 0.2473 (2) | 0.68715 (9) | 0.66209 (13) | 0.0195 (3) | |
H4A | 0.1114 | 0.7215 | 0.6217 | 0.023* | |
H4B | 0.3714 | 0.7233 | 0.6171 | 0.023* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0541 (7) | 0.0204 (5) | 0.0138 (4) | 0.0012 (5) | 0.0027 (5) | −0.0005 (3) |
O2 | 0.0511 (7) | 0.0159 (4) | 0.0165 (4) | −0.0009 (5) | 0.0023 (5) | 0.0038 (3) |
O3 | 0.0685 (8) | 0.0138 (5) | 0.0205 (5) | −0.0018 (5) | −0.0029 (5) | −0.0009 (3) |
O4 | 0.0613 (8) | 0.0193 (5) | 0.0176 (5) | −0.0027 (5) | 0.0020 (5) | −0.0013 (4) |
O5 | 0.0748 (9) | 0.0209 (5) | 0.0152 (5) | −0.0005 (6) | 0.0078 (6) | 0.0007 (4) |
N1 | 0.0350 (6) | 0.0104 (5) | 0.0152 (5) | 0.0000 (5) | 0.0003 (5) | −0.0011 (4) |
N2 | 0.0317 (6) | 0.0143 (5) | 0.0117 (5) | −0.0003 (5) | 0.0020 (4) | −0.0007 (4) |
C1 | 0.0259 (7) | 0.0152 (5) | 0.0157 (6) | 0.0012 (5) | 0.0004 (5) | 0.0006 (4) |
C2 | 0.0259 (7) | 0.0146 (5) | 0.0158 (5) | 0.0003 (5) | 0.0007 (5) | 0.0000 (4) |
C3 | 0.0287 (7) | 0.0141 (5) | 0.0178 (6) | 0.0007 (5) | −0.0002 (5) | 0.0006 (4) |
C4 | 0.0317 (7) | 0.0119 (5) | 0.0149 (6) | 0.0002 (5) | −0.0001 (5) | 0.0027 (4) |
O1—C1 | 1.2195 (15) | N1—C2 | 1.3781 (16) |
O2—C2 | 1.2156 (15) | N2—H2N | 0.858 (18) |
O3—C3 | 1.2153 (16) | N2—C2 | 1.3704 (16) |
O4—H1O | 0.83 (2) | N2—C3 | 1.3651 (15) |
O4—H2O | 0.82 (2) | C1—C4 | 1.5018 (16) |
O5—H3O | 0.83 (2) | C3—C4 | 1.5026 (17) |
O5—H4O | 0.82 (2) | C4—H4A | 0.9900 |
N1—H1N | 0.838 (18) | C4—H4B | 0.9900 |
N1—C1 | 1.3622 (15) | ||
H1O—O4—H2O | 110 (2) | O2—C2—N2 | 122.09 (12) |
H3O—O5—H4O | 107 (2) | N1—C2—N2 | 117.01 (11) |
H1N—N1—C1 | 118.5 (11) | O3—C3—N2 | 119.57 (12) |
H1N—N1—C2 | 115.7 (11) | O3—C3—C4 | 123.15 (11) |
C1—N1—C2 | 125.75 (10) | N2—C3—C4 | 117.27 (10) |
H2N—N2—C2 | 118.5 (11) | C1—C4—C3 | 116.19 (10) |
H2N—N2—C3 | 115.6 (11) | C1—C4—H4A | 108.2 |
C2—N2—C3 | 125.94 (11) | C1—C4—H4B | 108.2 |
O1—C1—N1 | 120.89 (11) | C3—C4—H4A | 108.2 |
O1—C1—C4 | 121.64 (11) | C3—C4—H4B | 108.2 |
N1—C1—C4 | 117.47 (10) | H4A—C4—H4B | 107.4 |
O2—C2—N1 | 120.90 (11) | ||
C2—N1—C1—O1 | 177.79 (14) | C2—N2—C3—O3 | −176.05 (15) |
C2—N1—C1—C4 | −3.1 (2) | C2—N2—C3—C4 | 4.7 (2) |
C3—N2—C2—O2 | 178.49 (15) | O1—C1—C4—C3 | −174.52 (14) |
C3—N2—C2—N1 | −1.0 (2) | N1—C1—C4—C3 | 6.3 (2) |
C1—N1—C2—O2 | −179.37 (14) | O3—C3—C4—C1 | 173.69 (15) |
C1—N1—C2—N2 | 0.2 (2) | N2—C3—C4—C1 | −7.0 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.83 (2) | 1.97 (2) | 2.7611 (14) | 161 (2) |
O4—H2O···O1ii | 0.82 (2) | 2.04 (2) | 2.8546 (14) | 171 (2) |
O5—H3O···O4 | 0.83 (2) | 1.91 (2) | 2.7397 (16) | 174 (2) |
O5—H4O···O1 | 0.82 (2) | 1.97 (2) | 2.7797 (15) | 167 (2) |
N1—H1N···O3iii | 0.838 (18) | 1.975 (18) | 2.8117 (15) | 176.5 (16) |
N2—H2N···O5iv | 0.858 (18) | 1.870 (18) | 2.7224 (14) | 172.3 (17) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.575 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 5464 reflections |
a = 6.1377 (5) Å | θ = 2.3–28.2° |
b = 12.7306 (11) Å | µ = 0.15 mm−1 |
c = 8.8641 (8) Å | T = 190 K |
β = 92.5280 (15)° | Block, colourless |
V = 691.94 (10) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2140 independent reflections |
Radiation source: sealed tube | 1930 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −8→8 |
Tmin = 0.782, Tmax = 0.978 | k = −16→16 |
9902 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: mixed |
wR(F2) = 0.105 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0601P)2 + 0.1202P] where P = (Fo2 + 2Fc2)/3 |
2140 reflections | (Δ/σ)max = 0.003 |
120 parameters | Δρmax = 0.26 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C4H4N2O3·2H2O | V = 691.94 (10) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1377 (5) Å | µ = 0.15 mm−1 |
b = 12.7306 (11) Å | T = 190 K |
c = 8.8641 (8) Å | 0.53 × 0.42 × 0.15 mm |
β = 92.5280 (15)° |
Bruker SMART 1K CCD diffractometer | 2140 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 1930 reflections with I > 2σ(I) |
Tmin = 0.782, Tmax = 0.978 | Rint = 0.024 |
9902 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.105 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.26 e Å−3 |
2140 reflections | Δρmin = −0.28 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2470 (2) | 0.55228 (6) | 0.47638 (9) | 0.0343 (3) | |
O2 | 0.23972 (19) | 0.44178 (6) | 0.95852 (9) | 0.0319 (2) | |
O3 | 0.2813 (2) | 0.79045 (6) | 0.88757 (10) | 0.0405 (3) | |
O4 | 0.2365 (2) | 0.88652 (7) | 0.24005 (10) | 0.0376 (3) | |
H1O | 0.249 (3) | 0.9176 (14) | 0.325 (2) | 0.045* | |
H2O | 0.242 (3) | 0.9292 (15) | 0.170 (2) | 0.045* | |
O5 | 0.2721 (2) | 0.67279 (8) | 0.21639 (10) | 0.0432 (3) | |
H3O | 0.257 (3) | 0.7361 (18) | 0.227 (2) | 0.052* | |
H4O | 0.257 (3) | 0.6450 (16) | 0.301 (2) | 0.052* | |
N1 | 0.23998 (19) | 0.49869 (7) | 0.71727 (10) | 0.0237 (2) | |
H1N | 0.235 (3) | 0.4360 (13) | 0.6896 (16) | 0.028* | |
N2 | 0.25388 (19) | 0.61724 (7) | 0.91976 (10) | 0.0225 (2) | |
H2N | 0.256 (3) | 0.6303 (12) | 1.0161 (18) | 0.027* | |
C1 | 0.2458 (2) | 0.57501 (8) | 0.60989 (12) | 0.0221 (2) | |
C2 | 0.2438 (2) | 0.51508 (8) | 0.87111 (12) | 0.0217 (2) | |
C3 | 0.2633 (2) | 0.70402 (8) | 0.83004 (13) | 0.0237 (3) | |
C4 | 0.2478 (2) | 0.68704 (8) | 0.66203 (11) | 0.0231 (3) | |
H4A | 0.1129 | 0.7214 | 0.6213 | 0.028* | |
H4B | 0.3725 | 0.7230 | 0.6174 | 0.028* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0644 (7) | 0.0225 (4) | 0.0160 (4) | 0.0010 (5) | 0.0024 (4) | −0.0005 (3) |
O2 | 0.0595 (7) | 0.0169 (4) | 0.0192 (4) | −0.0010 (4) | 0.0026 (4) | 0.0043 (3) |
O3 | 0.0834 (9) | 0.0152 (4) | 0.0226 (4) | −0.0019 (5) | −0.0021 (5) | −0.0008 (3) |
O4 | 0.0712 (8) | 0.0223 (4) | 0.0193 (4) | −0.0017 (5) | 0.0024 (5) | −0.0008 (3) |
O5 | 0.0897 (10) | 0.0232 (4) | 0.0172 (4) | −0.0008 (6) | 0.0075 (5) | 0.0002 (3) |
N1 | 0.0412 (6) | 0.0125 (4) | 0.0173 (5) | −0.0008 (4) | 0.0015 (4) | −0.0011 (3) |
N2 | 0.0379 (6) | 0.0157 (4) | 0.0139 (4) | −0.0002 (4) | 0.0019 (4) | −0.0003 (3) |
C1 | 0.0312 (6) | 0.0177 (5) | 0.0174 (5) | 0.0003 (5) | 0.0007 (5) | 0.0008 (4) |
C2 | 0.0312 (6) | 0.0165 (5) | 0.0173 (5) | −0.0001 (5) | 0.0014 (4) | 0.0008 (4) |
C3 | 0.0359 (7) | 0.0150 (5) | 0.0200 (5) | 0.0006 (5) | 0.0001 (5) | 0.0010 (4) |
C4 | 0.0379 (7) | 0.0144 (5) | 0.0170 (5) | 0.0004 (5) | 0.0005 (5) | 0.0028 (4) |
O1—C1 | 1.2186 (14) | N1—C2 | 1.3787 (14) |
O2—C2 | 1.2139 (13) | N2—H2N | 0.870 (16) |
O3—C3 | 1.2157 (14) | N2—C2 | 1.3707 (14) |
O4—H1O | 0.852 (18) | N2—C3 | 1.3640 (13) |
O4—H2O | 0.827 (19) | C1—C4 | 1.4992 (14) |
O5—H3O | 0.82 (2) | C3—C4 | 1.5037 (15) |
O5—H4O | 0.84 (2) | C4—H4A | 0.9900 |
N1—H1N | 0.835 (16) | C4—H4B | 0.9900 |
N1—C1 | 1.3617 (14) | ||
H1O—O4—H2O | 110.8 (18) | O2—C2—N2 | 122.04 (10) |
H3O—O5—H4O | 107.2 (18) | N1—C2—N2 | 116.96 (9) |
H1N—N1—C1 | 118.6 (10) | O3—C3—N2 | 119.60 (10) |
H1N—N1—C2 | 115.7 (10) | O3—C3—C4 | 123.10 (10) |
C1—N1—C2 | 125.70 (9) | N2—C3—C4 | 117.29 (9) |
H2N—N2—C2 | 119.3 (10) | C1—C4—C3 | 116.20 (9) |
H2N—N2—C3 | 114.7 (10) | C1—C4—H4A | 108.2 |
C2—N2—C3 | 125.99 (9) | C1—C4—H4B | 108.2 |
O1—C1—N1 | 120.72 (10) | C3—C4—H4A | 108.2 |
O1—C1—C4 | 121.67 (9) | C3—C4—H4B | 108.2 |
N1—C1—C4 | 117.60 (9) | H4A—C4—H4B | 107.4 |
O2—C2—N1 | 121.00 (10) | ||
C2—N1—C1—O1 | 178.21 (13) | C2—N2—C3—O3 | −176.78 (13) |
C2—N1—C1—C4 | −2.6 (2) | C2—N2—C3—C4 | 3.9 (2) |
C3—N2—C2—O2 | 178.68 (14) | O1—C1—C4—C3 | −175.51 (13) |
C3—N2—C2—N1 | −0.9 (2) | N1—C1—C4—C3 | 5.29 (18) |
C1—N1—C2—O2 | −179.41 (13) | O3—C3—C4—C1 | 174.83 (13) |
C1—N1—C2—N2 | 0.2 (2) | N2—C3—C4—C1 | −5.89 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.852 (18) | 1.941 (19) | 2.7606 (13) | 161.1 (17) |
O4—H2O···O1ii | 0.827 (19) | 2.037 (19) | 2.8567 (12) | 170.7 (17) |
O5—H3O···O4 | 0.82 (2) | 1.92 (2) | 2.7384 (14) | 175 (2) |
O5—H4O···O1 | 0.84 (2) | 1.96 (2) | 2.7785 (13) | 167.3 (18) |
N1—H1N···O3iii | 0.835 (16) | 1.976 (16) | 2.8103 (13) | 176.8 (14) |
N2—H2N···O5iv | 0.870 (16) | 1.854 (16) | 2.7204 (13) | 173.7 (15) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.583 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 4075 reflections |
a = 6.1313 (12) Å | θ = 2.3–28.2° |
b = 12.703 (2) Å | µ = 0.15 mm−1 |
c = 8.8456 (17) Å | T = 200 K |
β = 92.187 (4)° | Block, colourless |
V = 688.5 (2) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2456 independent reflections |
Radiation source: fine-focus sealed tube | 2397 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −7→7 |
Tmin = 0.553, Tmax = 0.978 | k = −16→16 |
7874 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.087 | Hydrogen site location: mixed |
wR(F2) = 0.197 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.31 | w = 1/[σ2(Fo2) + (0.0377P)2 + 1.4289P] where P = (Fo2 + 2Fc2)/3 |
2456 reflections | (Δ/σ)max = 0.004 |
120 parameters | Δρmax = 0.50 e Å−3 |
0 restraints | Δρmin = −0.58 e Å−3 |
C4H4N2O3·2H2O | V = 688.5 (2) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1313 (12) Å | µ = 0.15 mm−1 |
b = 12.703 (2) Å | T = 200 K |
c = 8.8456 (17) Å | 0.53 × 0.42 × 0.15 mm |
β = 92.187 (4)° |
Bruker SMART 1K CCD diffractometer | 2456 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 2397 reflections with I > 2σ(I) |
Tmin = 0.553, Tmax = 0.978 | Rint = 0.029 |
7874 measured reflections |
R[F2 > 2σ(F2)] = 0.087 | 0 restraints |
wR(F2) = 0.197 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.31 | Δρmax = 0.50 e Å−3 |
2456 reflections | Δρmin = −0.58 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2471 (6) | 0.55228 (17) | 0.4762 (2) | 0.0314 (6) | |
O2 | 0.2414 (5) | 0.44196 (16) | 0.9585 (2) | 0.0296 (6) | |
O3 | 0.2771 (6) | 0.79017 (17) | 0.8872 (3) | 0.0385 (7) | |
O4 | 0.2382 (6) | 0.88663 (18) | 0.2402 (3) | 0.0346 (7) | |
H1O | 0.256 (9) | 0.921 (3) | 0.322 (5) | 0.042* | |
H2O | 0.249 (9) | 0.930 (3) | 0.175 (5) | 0.042* | |
O5 | 0.2702 (7) | 0.6728 (2) | 0.2160 (3) | 0.0415 (8) | |
H3O | 0.246 (9) | 0.733 (4) | 0.225 (5) | 0.050* | |
H4O | 0.245 (9) | 0.645 (4) | 0.293 (5) | 0.050* | |
N1 | 0.2413 (6) | 0.49912 (18) | 0.7177 (3) | 0.0206 (6) | |
H1N | 0.243 (7) | 0.439 (3) | 0.689 (4) | 0.025* | |
N2 | 0.2537 (5) | 0.61703 (18) | 0.9196 (3) | 0.0193 (5) | |
H2N | 0.255 (7) | 0.630 (3) | 1.013 (4) | 0.023* | |
C1 | 0.2456 (6) | 0.5748 (2) | 0.6096 (3) | 0.0177 (6) | |
C2 | 0.2444 (6) | 0.5154 (2) | 0.8710 (3) | 0.0179 (6) | |
C3 | 0.2612 (6) | 0.7044 (2) | 0.8301 (3) | 0.0202 (6) | |
C4 | 0.2485 (6) | 0.6873 (2) | 0.6626 (3) | 0.0190 (6) | |
H4A | 0.3748 | 0.7230 | 0.6185 | 0.023* | |
H4B | 0.1148 | 0.7223 | 0.6212 | 0.023* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0622 (18) | 0.0206 (11) | 0.0116 (10) | 0.0009 (13) | 0.0049 (13) | −0.0011 (8) |
O2 | 0.0586 (17) | 0.0145 (10) | 0.0156 (10) | 0.0024 (12) | 0.0010 (13) | 0.0043 (8) |
O3 | 0.082 (2) | 0.0126 (10) | 0.0204 (11) | −0.0023 (14) | −0.0025 (15) | −0.0021 (9) |
O4 | 0.069 (2) | 0.0170 (11) | 0.0177 (11) | −0.0053 (14) | 0.0011 (15) | −0.0022 (9) |
O5 | 0.091 (3) | 0.0211 (12) | 0.0130 (11) | −0.0004 (17) | 0.0104 (16) | 0.0018 (9) |
N1 | 0.0391 (17) | 0.0070 (10) | 0.0156 (11) | 0.0002 (12) | −0.0006 (13) | −0.0019 (8) |
N2 | 0.0328 (16) | 0.0137 (11) | 0.0113 (11) | 0.0024 (12) | 0.0003 (12) | −0.0027 (9) |
C1 | 0.0237 (17) | 0.0126 (12) | 0.0170 (13) | 0.0049 (13) | 0.0017 (14) | 0.0000 (10) |
C2 | 0.0250 (17) | 0.0143 (12) | 0.0142 (12) | −0.0008 (13) | −0.0011 (14) | −0.0025 (10) |
C3 | 0.0281 (18) | 0.0132 (12) | 0.0193 (13) | −0.0003 (14) | 0.0017 (14) | −0.0005 (10) |
C4 | 0.0337 (19) | 0.0085 (11) | 0.0144 (13) | −0.0024 (14) | −0.0060 (15) | 0.0024 (9) |
O1—C1 | 1.215 (3) | N1—H1N | 0.80 (4) |
O2—C2 | 1.212 (3) | N2—C2 | 1.362 (3) |
O3—C3 | 1.203 (4) | N2—C3 | 1.365 (4) |
O4—H1O | 0.85 (5) | N2—H2N | 0.85 (4) |
O4—H2O | 0.80 (5) | C1—C4 | 1.504 (4) |
O5—H3O | 0.78 (5) | C3—C4 | 1.497 (4) |
O5—H4O | 0.79 (5) | C4—H4A | 0.9900 |
N1—C1 | 1.357 (4) | C4—H4B | 0.9900 |
N1—C2 | 1.371 (4) | ||
H1O—O4—H2O | 104 (4) | O2—C2—N1 | 121.0 (2) |
H3O—O5—H4O | 108 (5) | N2—C2—N1 | 117.0 (2) |
C1—N1—C2 | 126.2 (2) | O3—C3—N2 | 119.8 (3) |
C1—N1—H1N | 117 (3) | O3—C3—C4 | 123.1 (3) |
C2—N1—H1N | 117 (3) | N2—C3—C4 | 117.1 (2) |
C2—N2—C3 | 126.1 (2) | C3—C4—C1 | 116.4 (2) |
C2—N2—H2N | 120 (2) | C3—C4—H4A | 108.2 |
C3—N2—H2N | 114 (2) | C1—C4—H4A | 108.2 |
O1—C1—N1 | 121.2 (2) | C3—C4—H4B | 108.2 |
O1—C1—C4 | 121.7 (2) | C1—C4—H4B | 108.2 |
N1—C1—C4 | 117.1 (2) | H4A—C4—H4B | 107.3 |
O2—C2—N2 | 122.0 (3) | ||
C2—N1—C1—O1 | 178.4 (4) | C2—N2—C3—O3 | −177.3 (4) |
C2—N1—C1—C4 | −1.6 (6) | C2—N2—C3—C4 | 2.8 (6) |
C3—N2—C2—O2 | 178.9 (4) | O3—C3—C4—C1 | 175.7 (4) |
C3—N2—C2—N1 | −0.3 (6) | N2—C3—C4—C1 | −4.4 (5) |
C1—N1—C2—O2 | −179.6 (4) | O1—C1—C4—C3 | −176.1 (4) |
C1—N1—C2—N2 | −0.3 (6) | N1—C1—C4—C3 | 3.9 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.85 (5) | 1.96 (5) | 2.755 (3) | 155 (4) |
O4—H2O···O1ii | 0.80 (5) | 2.05 (5) | 2.848 (3) | 173 (5) |
O5—H3O···O4 | 0.78 (5) | 1.96 (5) | 2.733 (3) | 170 (6) |
O5—H4O···O1 | 0.79 (5) | 2.00 (5) | 2.772 (3) | 165 (5) |
N1—H1N···O3iii | 0.80 (4) | 2.01 (4) | 2.813 (3) | 175 (4) |
N2—H2N···O5iv | 0.85 (4) | 1.87 (4) | 2.714 (3) | 174 (4) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.566 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 2331 reflections |
a = 6.1538 (15) Å | θ = 2.3–28.3° |
b = 12.747 (3) Å | µ = 0.15 mm−1 |
c = 8.877 (2) Å | T = 210 K |
β = 91.627 (4)° | Block, colourless |
V = 696.0 (3) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2165 independent reflections |
Radiation source: sealed tube | 2018 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −8→8 |
Tmin = 0.574, Tmax = 0.979 | k = −16→16 |
7495 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.066 | Hydrogen site location: mixed |
wR(F2) = 0.152 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.28 | w = 1/[σ2(Fo2) + (0.0301P)2 + 0.8768P] where P = (Fo2 + 2Fc2)/3 |
2165 reflections | (Δ/σ)max = 0.007 |
120 parameters | Δρmax = 0.42 e Å−3 |
0 restraints | Δρmin = −0.42 e Å−3 |
C4H4N2O3·2H2O | V = 696.0 (3) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1538 (15) Å | µ = 0.15 mm−1 |
b = 12.747 (3) Å | T = 210 K |
c = 8.877 (2) Å | 0.53 × 0.42 × 0.15 mm |
β = 91.627 (4)° |
Bruker SMART 1K CCD diffractometer | 2165 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 2018 reflections with I > 2σ(I) |
Tmin = 0.574, Tmax = 0.979 | Rint = 0.027 |
7495 measured reflections |
R[F2 > 2σ(F2)] = 0.066 | 0 restraints |
wR(F2) = 0.152 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.28 | Δρmax = 0.42 e Å−3 |
2165 reflections | Δρmin = −0.42 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2478 (5) | 0.55246 (14) | 0.47661 (18) | 0.0357 (5) | |
O2 | 0.2437 (5) | 0.44171 (13) | 0.95843 (18) | 0.0330 (5) | |
O3 | 0.2708 (5) | 0.79040 (14) | 0.8872 (2) | 0.0435 (6) | |
O4 | 0.2409 (6) | 0.88652 (15) | 0.2400 (2) | 0.0396 (5) | |
H1O | 0.253 (7) | 0.919 (3) | 0.319 (4) | 0.048* | |
H2O | 0.258 (7) | 0.931 (3) | 0.172 (4) | 0.048* | |
O5 | 0.2655 (6) | 0.67270 (17) | 0.2158 (2) | 0.0468 (7) | |
H3O | 0.249 (8) | 0.735 (3) | 0.223 (4) | 0.056* | |
H4O | 0.247 (8) | 0.647 (3) | 0.295 (4) | 0.056* | |
N1 | 0.2436 (5) | 0.49889 (14) | 0.7172 (2) | 0.0233 (5) | |
H1N | 0.243 (6) | 0.436 (2) | 0.689 (3) | 0.028* | |
N2 | 0.2527 (5) | 0.61701 (14) | 0.9194 (2) | 0.0224 (5) | |
H2N | 0.256 (6) | 0.628 (2) | 1.012 (4) | 0.027* | |
C1 | 0.2468 (5) | 0.57500 (16) | 0.6095 (2) | 0.0214 (5) | |
C2 | 0.2458 (5) | 0.51537 (16) | 0.8710 (2) | 0.0202 (5) | |
C3 | 0.2578 (5) | 0.70429 (17) | 0.8300 (3) | 0.0239 (5) | |
C4 | 0.2484 (6) | 0.68711 (16) | 0.6624 (2) | 0.0225 (5) | |
H4A | 0.3738 | 0.7223 | 0.6193 | 0.027* | |
H4B | 0.1173 | 0.7216 | 0.6213 | 0.027* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0721 (15) | 0.0221 (9) | 0.0132 (8) | 0.0030 (13) | 0.0049 (13) | −0.0006 (7) |
O2 | 0.0666 (14) | 0.0159 (8) | 0.0166 (8) | 0.0016 (12) | 0.0037 (12) | 0.0041 (7) |
O3 | 0.0956 (18) | 0.0135 (8) | 0.0209 (9) | −0.0002 (14) | −0.0035 (15) | −0.0014 (7) |
O4 | 0.0791 (16) | 0.0201 (9) | 0.0198 (9) | −0.0052 (13) | 0.0026 (15) | −0.0029 (7) |
O5 | 0.102 (2) | 0.0243 (10) | 0.0144 (9) | −0.0023 (18) | 0.0087 (16) | 0.0015 (7) |
N1 | 0.0440 (13) | 0.0087 (8) | 0.0172 (9) | −0.0004 (12) | 0.0012 (12) | −0.0008 (7) |
N2 | 0.0418 (13) | 0.0146 (9) | 0.0108 (9) | 0.0040 (11) | 0.0027 (11) | −0.0014 (7) |
C1 | 0.0317 (14) | 0.0149 (10) | 0.0178 (11) | 0.0029 (12) | 0.0032 (13) | 0.0009 (8) |
C2 | 0.0316 (14) | 0.0143 (10) | 0.0146 (10) | 0.0004 (12) | 0.0023 (12) | −0.0006 (8) |
C3 | 0.0383 (15) | 0.0137 (10) | 0.0196 (11) | 0.0022 (13) | 0.0018 (13) | 0.0005 (8) |
C4 | 0.0400 (15) | 0.0120 (9) | 0.0153 (10) | −0.0033 (13) | −0.0006 (13) | 0.0025 (8) |
O1—C1 | 1.214 (3) | N1—C2 | 1.381 (3) |
O2—C2 | 1.218 (3) | N2—H2N | 0.83 (3) |
O3—C3 | 1.211 (3) | N2—C2 | 1.365 (3) |
O4—H1O | 0.81 (4) | N2—C3 | 1.367 (3) |
O4—H2O | 0.83 (4) | C1—C4 | 1.504 (3) |
O5—H3O | 0.80 (4) | C3—C4 | 1.503 (3) |
O5—H4O | 0.79 (4) | C4—H4A | 0.9800 |
N1—H1N | 0.84 (3) | C4—H4B | 0.9800 |
N1—C1 | 1.362 (3) | ||
H1O—O4—H2O | 106 (3) | O2—C2—N2 | 122.1 (2) |
H3O—O5—H4O | 109 (4) | N1—C2—N2 | 117.05 (19) |
H1N—N1—C1 | 118.2 (19) | O3—C3—N2 | 119.8 (2) |
H1N—N1—C2 | 116.0 (19) | O3—C3—C4 | 123.2 (2) |
C1—N1—C2 | 125.83 (19) | N2—C3—C4 | 117.06 (19) |
H2N—N2—C2 | 118 (2) | C1—C4—C3 | 116.56 (18) |
H2N—N2—C3 | 115 (2) | C1—C4—H4A | 108.2 |
C2—N2—C3 | 126.19 (19) | C1—C4—H4B | 108.2 |
O1—C1—N1 | 120.9 (2) | C3—C4—H4A | 108.2 |
O1—C1—C4 | 121.9 (2) | C3—C4—H4B | 108.2 |
N1—C1—C4 | 117.22 (19) | H4A—C4—H4B | 107.3 |
O2—C2—N1 | 120.8 (2) | ||
C2—N1—C1—O1 | 178.9 (3) | C2—N2—C3—O3 | −177.6 (3) |
C2—N1—C1—C4 | −1.2 (5) | C2—N2—C3—C4 | 1.9 (5) |
C3—N2—C2—O2 | 179.3 (3) | O3—C3—C4—C1 | 176.2 (3) |
C3—N2—C2—N1 | 0.0 (5) | N2—C3—C4—C1 | −3.3 (5) |
C1—N1—C2—O2 | −179.6 (3) | O1—C1—C4—C3 | −177.1 (3) |
C1—N1—C2—N2 | −0.3 (5) | N1—C1—C4—C3 | 3.0 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.81 (4) | 2.00 (4) | 2.767 (3) | 157 (3) |
O4—H2O···O1ii | 0.83 (4) | 2.04 (4) | 2.861 (3) | 169 (4) |
O5—H3O···O4 | 0.80 (4) | 1.94 (4) | 2.739 (3) | 174 (5) |
O5—H4O···O1 | 0.79 (4) | 2.01 (4) | 2.782 (3) | 166 (4) |
N1—H1N···O3iii | 0.84 (3) | 1.98 (3) | 2.815 (3) | 176 (3) |
N2—H2N···O5iv | 0.83 (3) | 1.90 (3) | 2.724 (3) | 173 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.564 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 3413 reflections |
a = 6.1580 (9) Å | θ = 2.3–28.3° |
b = 12.7515 (18) Å | µ = 0.15 mm−1 |
c = 8.8763 (13) Å | T = 215 K |
β = 91.263 (3)° | Block, colourless |
V = 696.83 (17) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2442 independent reflections |
Radiation source: sealed tube | 2299 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −8→8 |
Tmin = 0.331, Tmax = 0.979 | k = −16→16 |
8726 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.069 | Hydrogen site location: mixed |
wR(F2) = 0.194 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.19 | w = 1/[σ2(Fo2) + (0.0892P)2 + 0.5663P] where P = (Fo2 + 2Fc2)/3 |
2442 reflections | (Δ/σ)max = 0.006 |
120 parameters | Δρmax = 0.41 e Å−3 |
0 restraints | Δρmin = −0.44 e Å−3 |
C4H4N2O3·2H2O | V = 696.83 (17) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1580 (9) Å | µ = 0.15 mm−1 |
b = 12.7515 (18) Å | T = 215 K |
c = 8.8763 (13) Å | 0.53 × 0.42 × 0.15 mm |
β = 91.263 (3)° |
Bruker SMART 1K CCD diffractometer | 2442 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 2299 reflections with I > 2σ(I) |
Tmin = 0.331, Tmax = 0.979 | Rint = 0.026 |
8726 measured reflections |
R[F2 > 2σ(F2)] = 0.069 | 0 restraints |
wR(F2) = 0.194 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.19 | Δρmax = 0.41 e Å−3 |
2442 reflections | Δρmin = −0.44 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2484 (4) | 0.55256 (12) | 0.47633 (17) | 0.0379 (5) | |
O2 | 0.2450 (4) | 0.44181 (11) | 0.95858 (16) | 0.0351 (4) | |
O3 | 0.2659 (5) | 0.79038 (12) | 0.8873 (2) | 0.0468 (6) | |
O4 | 0.2431 (4) | 0.88661 (13) | 0.2403 (2) | 0.0413 (5) | |
H1O | 0.247 (6) | 0.920 (3) | 0.324 (4) | 0.050* | |
H2O | 0.252 (6) | 0.930 (3) | 0.168 (4) | 0.050* | |
O5 | 0.2611 (5) | 0.67261 (15) | 0.21545 (19) | 0.0497 (6) | |
H3O | 0.255 (7) | 0.738 (3) | 0.223 (4) | 0.060* | |
H4O | 0.249 (7) | 0.647 (3) | 0.299 (4) | 0.060* | |
N1 | 0.2454 (4) | 0.49886 (13) | 0.71734 (18) | 0.0252 (4) | |
H1N | 0.242 (5) | 0.437 (2) | 0.690 (3) | 0.030* | |
N2 | 0.2523 (4) | 0.61692 (12) | 0.91937 (18) | 0.0241 (4) | |
H2N | 0.249 (5) | 0.630 (2) | 1.011 (3) | 0.029* | |
C1 | 0.2481 (4) | 0.57491 (14) | 0.6098 (2) | 0.0234 (4) | |
C2 | 0.2470 (4) | 0.51546 (14) | 0.8712 (2) | 0.0224 (4) | |
C3 | 0.2568 (5) | 0.70427 (14) | 0.8298 (2) | 0.0255 (5) | |
C4 | 0.2490 (5) | 0.68708 (14) | 0.6624 (2) | 0.0247 (5) | |
H4A | 0.3747 | 0.7223 | 0.6192 | 0.030* | |
H4B | 0.1184 | 0.7215 | 0.6212 | 0.030* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0783 (13) | 0.0225 (8) | 0.0129 (7) | 0.0007 (10) | 0.0032 (10) | −0.0007 (6) |
O2 | 0.0739 (13) | 0.0154 (7) | 0.0161 (7) | 0.0005 (9) | 0.0013 (10) | 0.0041 (5) |
O3 | 0.1051 (17) | 0.0130 (7) | 0.0221 (8) | −0.0005 (11) | −0.0020 (12) | −0.0022 (6) |
O4 | 0.0844 (14) | 0.0199 (8) | 0.0198 (8) | −0.0022 (10) | 0.0033 (12) | −0.0030 (6) |
O5 | 0.1124 (19) | 0.0234 (9) | 0.0136 (8) | −0.0007 (13) | 0.0070 (13) | 0.0014 (6) |
N1 | 0.0505 (12) | 0.0086 (7) | 0.0164 (8) | −0.0002 (9) | 0.0014 (10) | −0.0008 (6) |
N2 | 0.0462 (11) | 0.0147 (8) | 0.0114 (7) | 0.0014 (9) | 0.0026 (9) | −0.0008 (6) |
C1 | 0.0392 (12) | 0.0146 (8) | 0.0164 (9) | 0.0015 (10) | 0.0015 (10) | 0.0014 (7) |
C2 | 0.0373 (12) | 0.0138 (8) | 0.0163 (9) | 0.0013 (9) | 0.0010 (10) | −0.0002 (6) |
C3 | 0.0444 (13) | 0.0125 (8) | 0.0196 (9) | 0.0002 (10) | 0.0011 (11) | 0.0012 (7) |
C4 | 0.0468 (13) | 0.0114 (8) | 0.0157 (9) | −0.0005 (10) | −0.0014 (11) | 0.0028 (6) |
O1—C1 | 1.219 (2) | N1—C2 | 1.382 (2) |
O2—C2 | 1.218 (2) | N2—H2N | 0.83 (3) |
O3—C3 | 1.211 (2) | N2—C2 | 1.363 (2) |
O4—H1O | 0.86 (4) | N2—C3 | 1.369 (2) |
O4—H2O | 0.85 (4) | C1—C4 | 1.504 (2) |
O5—H3O | 0.83 (4) | C3—C4 | 1.502 (3) |
O5—H4O | 0.82 (4) | C4—H4A | 0.9800 |
N1—H1N | 0.83 (3) | C4—H4B | 0.9800 |
N1—C1 | 1.361 (2) | ||
H1O—O4—H2O | 109 (3) | O2—C2—N2 | 122.17 (18) |
H3O—O5—H4O | 109 (4) | N1—C2—N2 | 117.08 (17) |
H1N—N1—C1 | 118.5 (19) | O3—C3—N2 | 119.63 (19) |
H1N—N1—C2 | 115.8 (19) | O3—C3—C4 | 123.30 (18) |
C1—N1—C2 | 125.73 (16) | N2—C3—C4 | 117.07 (16) |
H2N—N2—C2 | 120 (2) | C1—C4—C3 | 116.45 (15) |
H2N—N2—C3 | 114 (2) | C1—C4—H4A | 108.2 |
C2—N2—C3 | 126.22 (17) | C1—C4—H4B | 108.2 |
O1—C1—N1 | 121.03 (18) | C3—C4—H4A | 108.2 |
O1—C1—C4 | 121.59 (17) | C3—C4—H4B | 108.2 |
N1—C1—C4 | 117.38 (16) | H4A—C4—H4B | 107.3 |
O2—C2—N1 | 120.74 (17) | ||
C2—N1—C1—O1 | 179.3 (3) | C2—N2—C3—O3 | −178.5 (3) |
C2—N1—C1—C4 | −1.1 (4) | C2—N2—C3—C4 | 1.8 (4) |
C3—N2—C2—O2 | 179.4 (3) | O3—C3—C4—C1 | 177.4 (3) |
C3—N2—C2—N1 | −0.2 (4) | N2—C3—C4—C1 | −2.9 (4) |
C1—N1—C2—O2 | −179.8 (3) | O1—C1—C4—C3 | −177.8 (3) |
C1—N1—C2—N2 | −0.2 (4) | N1—C1—C4—C3 | 2.6 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.86 (4) | 1.95 (4) | 2.763 (2) | 159 (3) |
O4—H2O···O1ii | 0.85 (4) | 2.02 (4) | 2.860 (2) | 169 (3) |
O5—H3O···O4 | 0.83 (4) | 1.91 (4) | 2.740 (3) | 179 (4) |
O5—H4O···O1 | 0.82 (4) | 1.98 (4) | 2.778 (2) | 166 (4) |
N1—H1N···O3iii | 0.83 (3) | 1.99 (3) | 2.816 (2) | 177 (3) |
N2—H2N···O5iv | 0.83 (3) | 1.89 (3) | 2.722 (2) | 173 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.569 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 2043 reflections |
a = 6.1567 (16) Å | θ = 2.3–28.5° |
b = 12.733 (3) Å | µ = 0.15 mm−1 |
c = 8.865 (2) Å | T = 216 K |
β = 91.180 (5)° | Block, colourless |
V = 694.8 (3) Å3 | 0.53 × 0.42 × 0.15 mm |
Z = 4 |
Bruker SMART 1K CCD diffractometer | 2209 independent reflections |
Radiation source: sealed tube | 2058 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
thin–slice ω scans | θmax = 28.7°, θmin = 2.8° |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | h = −8→8 |
Tmin = 0.492, Tmax = 0.979 | k = −16→16 |
7321 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.068 | Hydrogen site location: mixed |
wR(F2) = 0.181 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.30 | w = 1/[σ2(Fo2) + (0.062P)2 + 0.4139P] where P = (Fo2 + 2Fc2)/3 |
2209 reflections | (Δ/σ)max = 0.002 |
120 parameters | Δρmax = 0.33 e Å−3 |
0 restraints | Δρmin = −0.47 e Å−3 |
C4H4N2O3·2H2O | V = 694.8 (3) Å3 |
Mr = 164.12 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 6.1567 (16) Å | µ = 0.15 mm−1 |
b = 12.733 (3) Å | T = 216 K |
c = 8.865 (2) Å | 0.53 × 0.42 × 0.15 mm |
β = 91.180 (5)° |
Bruker SMART 1K CCD diffractometer | 2209 independent reflections |
Absorption correction: multi-scan TWINABS; Sheldrick (2002) | 2058 reflections with I > 2σ(I) |
Tmin = 0.492, Tmax = 0.979 | Rint = 0.024 |
7321 measured reflections |
R[F2 > 2σ(F2)] = 0.068 | 0 restraints |
wR(F2) = 0.181 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.30 | Δρmax = 0.33 e Å−3 |
2209 reflections | Δρmin = −0.47 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2511 (5) | 0.55242 (13) | 0.47649 (18) | 0.0372 (5) | |
O2 | 0.2545 (5) | 0.44172 (12) | 0.95856 (18) | 0.0340 (5) | |
O3 | 0.2341 (5) | 0.79039 (13) | 0.8873 (2) | 0.0458 (6) | |
O4 | 0.2570 (5) | 0.88662 (14) | 0.2402 (2) | 0.0401 (5) | |
H1O | 0.247 (7) | 0.918 (3) | 0.324 (4) | 0.048* | |
H2O | 0.230 (7) | 0.929 (3) | 0.171 (4) | 0.048* | |
O5 | 0.2372 (6) | 0.67273 (16) | 0.2155 (2) | 0.0483 (6) | |
H3O | 0.266 (8) | 0.732 (4) | 0.225 (5) | 0.058* | |
H4O | 0.265 (8) | 0.647 (3) | 0.299 (5) | 0.058* | |
N1 | 0.2539 (5) | 0.49891 (14) | 0.7176 (2) | 0.0244 (4) | |
H1N | 0.251 (6) | 0.438 (3) | 0.689 (3) | 0.029* | |
N2 | 0.2481 (5) | 0.61712 (13) | 0.9195 (2) | 0.0233 (4) | |
H2N | 0.243 (6) | 0.627 (2) | 1.016 (4) | 0.028* | |
C1 | 0.2529 (5) | 0.57487 (15) | 0.6098 (2) | 0.0215 (4) | |
C2 | 0.2531 (5) | 0.51522 (15) | 0.8710 (2) | 0.0214 (4) | |
C3 | 0.2434 (5) | 0.70403 (16) | 0.8296 (3) | 0.0250 (5) | |
C4 | 0.2504 (6) | 0.68705 (15) | 0.6623 (2) | 0.0235 (5) | |
H4A | 0.3802 | 0.7220 | 0.6245 | 0.028* | |
H4B | 0.1238 | 0.7218 | 0.6157 | 0.028* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0750 (13) | 0.0221 (8) | 0.0145 (8) | −0.0034 (13) | −0.0035 (14) | −0.0006 (6) |
O2 | 0.0684 (12) | 0.0152 (8) | 0.0182 (8) | −0.0018 (11) | −0.0040 (14) | 0.0039 (6) |
O3 | 0.1024 (17) | 0.0116 (8) | 0.0235 (9) | 0.0022 (14) | 0.0027 (17) | −0.0015 (7) |
O4 | 0.0789 (14) | 0.0198 (8) | 0.0213 (8) | 0.0064 (13) | −0.0040 (17) | −0.0016 (7) |
O5 | 0.1052 (19) | 0.0227 (9) | 0.0166 (9) | 0.0006 (17) | −0.0104 (18) | 0.0011 (7) |
N1 | 0.0474 (12) | 0.0087 (8) | 0.0172 (9) | −0.0004 (12) | 0.0012 (13) | −0.0003 (6) |
N2 | 0.0437 (11) | 0.0130 (8) | 0.0132 (8) | −0.0026 (11) | 0.0020 (12) | −0.0011 (6) |
C1 | 0.0333 (12) | 0.0140 (9) | 0.0169 (10) | −0.0039 (12) | −0.0017 (13) | 0.0006 (7) |
C2 | 0.0346 (12) | 0.0124 (9) | 0.0172 (9) | −0.0005 (11) | 0.0015 (14) | −0.0006 (7) |
C3 | 0.0421 (13) | 0.0124 (9) | 0.0203 (10) | −0.0028 (13) | −0.0038 (15) | 0.0005 (8) |
C4 | 0.0417 (13) | 0.0114 (9) | 0.0176 (10) | 0.0035 (13) | 0.0034 (14) | 0.0031 (7) |
O1—C1 | 1.215 (3) | N1—C2 | 1.376 (3) |
O2—C2 | 1.216 (3) | N2—H2N | 0.87 (3) |
O3—C3 | 1.215 (3) | N2—C2 | 1.367 (3) |
O4—H1O | 0.85 (4) | N2—C3 | 1.364 (3) |
O4—H2O | 0.83 (4) | C1—C4 | 1.503 (3) |
O5—H3O | 0.78 (4) | C3—C4 | 1.500 (3) |
O5—H4O | 0.82 (4) | C4—H4A | 0.9800 |
N1—H1N | 0.81 (3) | C4—H4B | 0.9800 |
N1—C1 | 1.360 (3) | ||
H1O—O4—H2O | 109 (3) | O2—C2—N2 | 122.0 (2) |
H3O—O5—H4O | 105 (4) | N1—C2—N2 | 117.03 (18) |
H1N—N1—C1 | 117 (2) | O3—C3—N2 | 119.3 (2) |
H1N—N1—C2 | 117 (2) | O3—C3—C4 | 123.3 (2) |
C1—N1—C2 | 125.97 (18) | N2—C3—C4 | 117.41 (18) |
H2N—N2—C2 | 117 (2) | C1—C4—C3 | 116.35 (17) |
H2N—N2—C3 | 117 (2) | C1—C4—H4A | 108.2 |
C2—N2—C3 | 125.90 (18) | C1—C4—H4B | 108.2 |
O1—C1—N1 | 121.06 (19) | C3—C4—H4A | 108.2 |
O1—C1—C4 | 121.65 (19) | C3—C4—H4B | 108.2 |
N1—C1—C4 | 117.29 (18) | H4A—C4—H4B | 107.4 |
O2—C2—N1 | 120.97 (19) | ||
C2—N1—C1—O1 | −179.1 (3) | C2—N2—C3—O3 | 178.3 (3) |
C2—N1—C1—C4 | −0.1 (5) | C2—N2—C3—C4 | −1.7 (5) |
C3—N2—C2—O2 | −179.1 (3) | O3—C3—C4—C1 | −177.7 (3) |
C3—N2—C2—N1 | 0.1 (5) | N2—C3—C4—C1 | 2.4 (5) |
C1—N1—C2—O2 | −179.9 (3) | O1—C1—C4—C3 | 177.5 (3) |
C1—N1—C2—N2 | 0.9 (5) | N1—C1—C4—C3 | −1.5 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.85 (4) | 1.95 (4) | 2.763 (3) | 161 (3) |
O4—H2O···O1ii | 0.83 (4) | 2.05 (4) | 2.854 (3) | 163 (4) |
O5—H3O···O4 | 0.78 (4) | 1.98 (4) | 2.735 (3) | 165 (5) |
O5—H4O···O1 | 0.82 (4) | 1.98 (4) | 2.775 (3) | 160 (4) |
N1—H1N···O3iii | 0.81 (3) | 2.01 (3) | 2.815 (3) | 176 (4) |
N2—H2N···O5iv | 0.87 (3) | 1.86 (3) | 2.719 (3) | 170 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.551 Mg m−3 |
Orthorhombic, Pmnb | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2bc 2a | Cell parameters from 4044 reflections |
a = 6.1770 (18) Å | θ = 2.3–28.4° |
b = 12.785 (4) Å | µ = 0.14 mm−1 |
c = 8.898 (3) Å | T = 217 K |
V = 702.7 (3) Å3 | Block, colourless |
Z = 4 | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 889 independent reflections |
Radiation source: sealed tube | 800 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.050 |
thin–slice ω scans | θmax = 28.4°, θmin = 2.8° |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | h = −8→7 |
Tmin = 0.321, Tmax = 0.979 | k = −16→16 |
5924 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.061 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.154 | Only H-atom coordinates refined |
S = 1.25 | w = 1/[σ2(Fo2) + (0.0547P)2 + 0.6287P] where P = (Fo2 + 2Fc2)/3 |
889 reflections | (Δ/σ)max < 0.001 |
82 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C4H4N2O3·2H2O | V = 702.7 (3) Å3 |
Mr = 164.12 | Z = 4 |
Orthorhombic, Pmnb | Mo Kα radiation |
a = 6.1770 (18) Å | µ = 0.14 mm−1 |
b = 12.785 (4) Å | T = 217 K |
c = 8.898 (3) Å | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 889 independent reflections |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | 800 reflections with I > 2σ(I) |
Tmin = 0.321, Tmax = 0.979 | Rint = 0.050 |
5924 measured reflections |
R[F2 > 2σ(F2)] = 0.061 | 0 restraints |
wR(F2) = 0.154 | Only H-atom coordinates refined |
S = 1.25 | Δρmax = 0.35 e Å−3 |
889 reflections | Δρmin = −0.28 e Å−3 |
82 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2500 | 0.55228 (16) | 0.4767 (2) | 0.0399 (7) | |
O2 | 0.2500 | 0.44191 (15) | 0.9584 (2) | 0.0366 (7) | |
O3 | 0.2500 | 0.79033 (16) | 0.8872 (2) | 0.0516 (9) | |
O4 | 0.2500 | 0.88660 (17) | 0.2405 (3) | 0.0435 (8) | |
H1O | 0.2500 | 0.914 (3) | 0.326 (5) | 0.052* | |
H2O | 0.2500 | 0.928 (4) | 0.169 (5) | 0.052* | |
O5 | 0.2500 | 0.6727 (2) | 0.2154 (3) | 0.0517 (9) | |
H3O | 0.2500 | 0.737 (4) | 0.221 (5) | 0.062* | |
H4O | 0.2500 | 0.651 (4) | 0.296 (6) | 0.062* | |
N1 | 0.2500 | 0.49888 (17) | 0.7173 (2) | 0.0262 (6) | |
H1N | 0.2500 | 0.438 (3) | 0.690 (4) | 0.031* | |
N2 | 0.2500 | 0.61720 (17) | 0.9196 (2) | 0.0252 (6) | |
H2N | 0.2500 | 0.629 (3) | 1.021 (4) | 0.030* | |
C1 | 0.2500 | 0.5749 (2) | 0.6102 (3) | 0.0237 (6) | |
C2 | 0.2500 | 0.51549 (19) | 0.8712 (3) | 0.0240 (6) | |
C3 | 0.2500 | 0.70413 (19) | 0.8298 (3) | 0.0277 (7) | |
C4 | 0.2500 | 0.6873 (2) | 0.6626 (3) | 0.0250 (7) | |
H1 | 0.124 (4) | 0.7146 (17) | 0.623 (3) | 0.030* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.085 (2) | 0.0214 (10) | 0.0134 (9) | 0.000 | 0.000 | −0.0003 (7) |
O2 | 0.077 (2) | 0.0145 (9) | 0.0184 (10) | 0.000 | 0.000 | 0.0042 (7) |
O3 | 0.120 (3) | 0.0122 (10) | 0.0228 (11) | 0.000 | 0.000 | −0.0013 (8) |
O4 | 0.091 (2) | 0.0200 (10) | 0.0195 (10) | 0.000 | 0.000 | −0.0012 (8) |
O5 | 0.117 (3) | 0.0227 (11) | 0.0158 (11) | 0.000 | 0.000 | 0.0008 (8) |
N1 | 0.0527 (18) | 0.0085 (10) | 0.0173 (11) | 0.000 | 0.000 | −0.0013 (8) |
N2 | 0.0500 (18) | 0.0129 (10) | 0.0128 (10) | 0.000 | 0.000 | −0.0002 (8) |
C1 | 0.0410 (19) | 0.0140 (11) | 0.0161 (12) | 0.000 | 0.000 | 0.0019 (9) |
C2 | 0.0425 (18) | 0.0130 (11) | 0.0164 (12) | 0.000 | 0.000 | 0.0001 (9) |
C3 | 0.053 (2) | 0.0110 (11) | 0.0194 (13) | 0.000 | 0.000 | 0.0017 (9) |
C4 | 0.045 (2) | 0.0117 (11) | 0.0178 (13) | 0.000 | 0.000 | 0.0023 (9) |
O1—C1 | 1.222 (3) | N1—C1 | 1.361 (3) |
O2—C2 | 1.219 (3) | N1—C2 | 1.386 (3) |
O3—C3 | 1.215 (3) | N2—H2N | 0.92 (4) |
O4—H1O | 0.84 (5) | N2—C2 | 1.370 (3) |
O4—H2O | 0.83 (5) | N2—C3 | 1.369 (3) |
O5—H3O | 0.82 (5) | C1—C4 | 1.511 (3) |
O5—H4O | 0.77 (5) | C3—C4 | 1.504 (4) |
N1—H1N | 0.81 (4) | C4—H1 | 0.92 (3) |
H1O—O4—H2O | 115 (4) | N1—C1—C4 | 117.6 (2) |
H3O—O5—H4O | 108 (5) | O2—C2—N1 | 120.7 (2) |
H1N—N1—C1 | 118 (3) | O2—C2—N2 | 122.2 (2) |
H1N—N1—C2 | 116 (3) | N1—C2—N2 | 117.1 (2) |
C1—N1—C2 | 125.6 (2) | O3—C3—N2 | 119.4 (3) |
H2N—N2—C2 | 118 (2) | O3—C3—C4 | 123.1 (2) |
H2N—N2—C3 | 116 (2) | N2—C3—C4 | 117.5 (2) |
C2—N2—C3 | 126.0 (2) | C1—C4—C3 | 116.2 (2) |
O1—C1—N1 | 120.7 (2) | C1—C4—H1 | 104.1 (15) |
O1—C1—C4 | 121.7 (2) | C3—C4—H1 | 108.7 (15) |
C2—N1—C1—O1 | 180.0 | C2—N2—C3—O3 | 180.000 (1) |
C2—N1—C1—C4 | 0.000 (1) | C2—N2—C3—C4 | 0.000 (2) |
C3—N2—C2—O2 | 180.000 (1) | O3—C3—C4—C1 | 180.000 (1) |
C3—N2—C2—N1 | 0.000 (1) | N2—C3—C4—C1 | 0.000 (1) |
C1—N1—C2—O2 | 180.0 | O1—C1—C4—C3 | 180.000 (1) |
C1—N1—C2—N2 | 0.000 (1) | N1—C1—C4—C3 | 0.000 (1) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.84 (5) | 1.95 (5) | 2.771 (3) | 166 (4) |
O4—H2O···O1ii | 0.83 (5) | 2.05 (5) | 2.867 (3) | 169 (4) |
O5—H3O···O4 | 0.82 (5) | 1.92 (6) | 2.744 (3) | 178 (5) |
O5—H4O···O1 | 0.77 (5) | 2.04 (5) | 2.788 (3) | 163 (5) |
N1—H1N···O3iii | 0.81 (4) | 2.01 (4) | 2.824 (3) | 178 (3) |
N2—H2N···O5iv | 0.92 (4) | 1.81 (4) | 2.726 (3) | 172 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.562 Mg m−3 |
Orthorhombic, Pmnb | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2bc 2a | Cell parameters from 3921 reflections |
a = 6.1626 (19) Å | θ = 2.3–28.3° |
b = 12.757 (4) Å | µ = 0.15 mm−1 |
c = 8.876 (3) Å | T = 218 K |
V = 697.8 (4) Å3 | Block, colourless |
Z = 4 | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 904 independent reflections |
Radiation source: sealed tube | 829 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
thin–slice ω scans | θmax = 28.2°, θmin = 2.8° |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | h = −7→8 |
Tmin = 0.351, Tmax = 0.979 | k = −16→16 |
5224 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.054 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.137 | Only H-atom coordinates refined |
S = 1.17 | w = 1/[σ2(Fo2) + (0.0601P)2 + 0.4239P] where P = (Fo2 + 2Fc2)/3 |
904 reflections | (Δ/σ)max < 0.001 |
82 parameters | Δρmax = 0.29 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C4H4N2O3·2H2O | V = 697.8 (4) Å3 |
Mr = 164.12 | Z = 4 |
Orthorhombic, Pmnb | Mo Kα radiation |
a = 6.1626 (19) Å | µ = 0.15 mm−1 |
b = 12.757 (4) Å | T = 218 K |
c = 8.876 (3) Å | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 904 independent reflections |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | 829 reflections with I > 2σ(I) |
Tmin = 0.351, Tmax = 0.979 | Rint = 0.047 |
5224 measured reflections |
R[F2 > 2σ(F2)] = 0.054 | 0 restraints |
wR(F2) = 0.137 | Only H-atom coordinates refined |
S = 1.17 | Δρmax = 0.29 e Å−3 |
904 reflections | Δρmin = −0.28 e Å−3 |
82 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2500 | 0.55228 (13) | 0.47671 (19) | 0.0397 (6) | |
O2 | 0.2500 | 0.44188 (12) | 0.95843 (18) | 0.0365 (5) | |
O3 | 0.2500 | 0.79037 (13) | 0.8871 (2) | 0.0510 (7) | |
O4 | 0.2500 | 0.88652 (15) | 0.2405 (2) | 0.0441 (6) | |
H1O | 0.2500 | 0.916 (3) | 0.324 (4) | 0.053* | |
H2O | 0.2500 | 0.928 (3) | 0.166 (4) | 0.053* | |
O5 | 0.2500 | 0.67261 (16) | 0.2155 (2) | 0.0524 (7) | |
H3O | 0.2500 | 0.735 (4) | 0.221 (5) | 0.063* | |
H4O | 0.2500 | 0.648 (3) | 0.298 (5) | 0.063* | |
N1 | 0.2500 | 0.49887 (14) | 0.7173 (2) | 0.0270 (5) | |
H1N | 0.2500 | 0.438 (3) | 0.689 (3) | 0.032* | |
N2 | 0.2500 | 0.61718 (14) | 0.9196 (2) | 0.0254 (5) | |
H2N | 0.2500 | 0.629 (2) | 1.022 (4) | 0.031* | |
C1 | 0.2500 | 0.57481 (16) | 0.6100 (2) | 0.0246 (5) | |
C2 | 0.2500 | 0.51532 (16) | 0.8711 (2) | 0.0238 (5) | |
C3 | 0.2500 | 0.70409 (16) | 0.8298 (3) | 0.0277 (6) | |
C4 | 0.2500 | 0.68728 (16) | 0.6624 (2) | 0.0258 (5) | |
H1 | 0.125 (4) | 0.7158 (14) | 0.622 (2) | 0.031* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0832 (16) | 0.0220 (9) | 0.0138 (8) | 0.000 | 0.000 | −0.0003 (6) |
O2 | 0.0762 (15) | 0.0151 (8) | 0.0181 (8) | 0.000 | 0.000 | 0.0045 (6) |
O3 | 0.117 (2) | 0.0130 (8) | 0.0227 (9) | 0.000 | 0.000 | −0.0016 (6) |
O4 | 0.0914 (18) | 0.0213 (9) | 0.0197 (8) | 0.000 | 0.000 | −0.0016 (7) |
O5 | 0.118 (2) | 0.0230 (9) | 0.0160 (9) | 0.000 | 0.000 | 0.0004 (7) |
N1 | 0.0548 (14) | 0.0097 (8) | 0.0166 (9) | 0.000 | 0.000 | −0.0014 (7) |
N2 | 0.0495 (13) | 0.0129 (8) | 0.0139 (8) | 0.000 | 0.000 | 0.0003 (7) |
C1 | 0.0436 (14) | 0.0148 (9) | 0.0154 (10) | 0.000 | 0.000 | 0.0013 (8) |
C2 | 0.0407 (14) | 0.0138 (9) | 0.0168 (10) | 0.000 | 0.000 | −0.0002 (8) |
C3 | 0.0516 (16) | 0.0120 (9) | 0.0195 (10) | 0.000 | 0.000 | 0.0016 (8) |
C4 | 0.0479 (16) | 0.0123 (9) | 0.0172 (10) | 0.000 | 0.000 | 0.0028 (8) |
O1—C1 | 1.217 (3) | N1—C1 | 1.359 (3) |
O2—C2 | 1.216 (3) | N1—C2 | 1.381 (3) |
O3—C3 | 1.213 (3) | N2—H2N | 0.92 (3) |
O4—H1O | 0.83 (4) | N2—C2 | 1.369 (3) |
O4—H2O | 0.85 (4) | N2—C3 | 1.366 (3) |
O5—H3O | 0.80 (5) | C1—C4 | 1.508 (3) |
O5—H4O | 0.79 (4) | C3—C4 | 1.500 (3) |
N1—H1N | 0.82 (3) | C4—H1 | 0.92 (2) |
H1O—O4—H2O | 114 (4) | N1—C1—C4 | 117.51 (19) |
H3O—O5—H4O | 110 (4) | O2—C2—N1 | 120.87 (19) |
H1N—N1—C1 | 118 (2) | O2—C2—N2 | 122.0 (2) |
H1N—N1—C2 | 117 (2) | N1—C2—N2 | 117.09 (19) |
C1—N1—C2 | 125.78 (18) | O3—C3—N2 | 119.4 (2) |
H2N—N2—C2 | 117.7 (19) | O3—C3—C4 | 123.0 (2) |
H2N—N2—C3 | 116.3 (19) | N2—C3—C4 | 117.52 (18) |
C2—N2—C3 | 125.92 (19) | C1—C4—C3 | 116.19 (18) |
O1—C1—N1 | 120.9 (2) | C1—C4—H1 | 104.8 (12) |
O1—C1—C4 | 121.63 (19) | C3—C4—H1 | 109.2 (13) |
C2—N1—C1—O1 | 180.0 | C2—N2—C3—O3 | 180.000 (1) |
C2—N1—C1—C4 | 0.000 (1) | C2—N2—C3—C4 | 0.000 (1) |
C3—N2—C2—O2 | 180.0 | O3—C3—C4—C1 | 180.000 (1) |
C3—N2—C2—N1 | 0.000 (1) | N2—C3—C4—C1 | 0.000 (1) |
C1—N1—C2—O2 | 180.0 | O1—C1—C4—C3 | 180.000 (1) |
C1—N1—C2—N2 | 0.000 (1) | N1—C1—C4—C3 | 0.000 (1) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.83 (4) | 1.96 (4) | 2.764 (3) | 162 (4) |
O4—H2O···O1ii | 0.85 (4) | 2.03 (4) | 2.861 (3) | 168 (4) |
O5—H3O···O4 | 0.80 (5) | 1.94 (5) | 2.738 (3) | 179 (4) |
O5—H4O···O1 | 0.79 (4) | 2.01 (5) | 2.780 (3) | 166 (4) |
N1—H1N···O3iii | 0.82 (3) | 2.00 (3) | 2.817 (3) | 178 (3) |
N2—H2N···O5iv | 0.92 (3) | 1.81 (3) | 2.720 (3) | 171 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.562 Mg m−3 |
Orthorhombic, Pmnb | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2bc 2a | Cell parameters from 4241 reflections |
a = 6.1624 (15) Å | θ = 2.3–28.3° |
b = 12.757 (3) Å | µ = 0.15 mm−1 |
c = 8.878 (2) Å | T = 219 K |
V = 697.9 (3) Å3 | Block, colourless |
Z = 4 | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 914 independent reflections |
Radiation source: sealed tube | 865 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.046 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan SADBAS; Sheldrick (2003) | h = −8→7 |
Tmin = 0.353, Tmax = 0.979 | k = −16→16 |
5236 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.066 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.158 | Only H-atom coordinates refined |
S = 1.32 | w = 1/[σ2(Fo2) + (0.0488P)2 + 0.7204P] where P = (Fo2 + 2Fc2)/3 |
914 reflections | (Δ/σ)max < 0.001 |
82 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.33 e Å−3 |
C4H4N2O3·2H2O | V = 697.9 (3) Å3 |
Mr = 164.12 | Z = 4 |
Orthorhombic, Pmnb | Mo Kα radiation |
a = 6.1624 (15) Å | µ = 0.15 mm−1 |
b = 12.757 (3) Å | T = 219 K |
c = 8.878 (2) Å | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 914 independent reflections |
Absorption correction: multi-scan SADBAS; Sheldrick (2003) | 865 reflections with I > 2σ(I) |
Tmin = 0.353, Tmax = 0.979 | Rint = 0.046 |
5236 measured reflections |
R[F2 > 2σ(F2)] = 0.066 | 0 restraints |
wR(F2) = 0.158 | Only H-atom coordinates refined |
S = 1.32 | Δρmax = 0.32 e Å−3 |
914 reflections | Δρmin = −0.33 e Å−3 |
82 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2500 | 0.55238 (17) | 0.4767 (2) | 0.0399 (7) | |
O2 | 0.2500 | 0.44185 (16) | 0.9583 (2) | 0.0368 (7) | |
O3 | 0.2500 | 0.79041 (16) | 0.8872 (3) | 0.0507 (9) | |
O4 | 0.2500 | 0.88667 (19) | 0.2402 (3) | 0.0436 (8) | |
H1O | 0.2500 | 0.916 (4) | 0.323 (6) | 0.052* | |
H2O | 0.2500 | 0.932 (4) | 0.165 (5) | 0.052* | |
O5 | 0.2500 | 0.6725 (2) | 0.2153 (3) | 0.0531 (10) | |
H3O | 0.2500 | 0.732 (5) | 0.222 (6) | 0.064* | |
H4O | 0.2500 | 0.650 (4) | 0.298 (6) | 0.064* | |
N1 | 0.2500 | 0.49897 (18) | 0.7173 (3) | 0.0268 (6) | |
H1N | 0.2500 | 0.438 (3) | 0.689 (4) | 0.032* | |
N2 | 0.2500 | 0.61709 (18) | 0.9195 (3) | 0.0257 (6) | |
H2N | 0.2500 | 0.628 (3) | 1.018 (5) | 0.031* | |
C1 | 0.2500 | 0.5748 (2) | 0.6099 (3) | 0.0239 (7) | |
C2 | 0.2500 | 0.5154 (2) | 0.8712 (3) | 0.0238 (7) | |
C3 | 0.2500 | 0.7041 (2) | 0.8296 (3) | 0.0275 (7) | |
C4 | 0.2500 | 0.6872 (2) | 0.6627 (3) | 0.0251 (7) | |
H1 | 0.128 (4) | 0.7142 (18) | 0.622 (3) | 0.030* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.084 (2) | 0.0219 (11) | 0.0135 (10) | 0.000 | 0.000 | −0.0001 (8) |
O2 | 0.0775 (19) | 0.0152 (10) | 0.0177 (10) | 0.000 | 0.000 | 0.0043 (8) |
O3 | 0.118 (3) | 0.0121 (10) | 0.0225 (11) | 0.000 | 0.000 | −0.0019 (8) |
O4 | 0.091 (2) | 0.0205 (11) | 0.0197 (11) | 0.000 | 0.000 | −0.0021 (9) |
O5 | 0.121 (3) | 0.0229 (11) | 0.0155 (11) | 0.000 | 0.000 | 0.0010 (9) |
N1 | 0.0550 (18) | 0.0086 (10) | 0.0167 (12) | 0.000 | 0.000 | −0.0011 (8) |
N2 | 0.0510 (17) | 0.0133 (11) | 0.0127 (11) | 0.000 | 0.000 | −0.0003 (9) |
C1 | 0.0419 (18) | 0.0135 (12) | 0.0164 (13) | 0.000 | 0.000 | 0.0012 (10) |
C2 | 0.0416 (18) | 0.0131 (12) | 0.0166 (13) | 0.000 | 0.000 | −0.0003 (10) |
C3 | 0.051 (2) | 0.0122 (12) | 0.0192 (13) | 0.000 | 0.000 | 0.0012 (10) |
C4 | 0.046 (2) | 0.0122 (12) | 0.0167 (13) | 0.000 | 0.000 | 0.0023 (10) |
O1—C1 | 1.217 (4) | N1—C1 | 1.359 (3) |
O2—C2 | 1.217 (3) | N1—C2 | 1.382 (4) |
O3—C3 | 1.214 (3) | N2—H2N | 0.88 (4) |
O4—H1O | 0.83 (5) | N2—C2 | 1.366 (3) |
O4—H2O | 0.89 (5) | N2—C3 | 1.367 (3) |
O5—H3O | 0.76 (6) | C1—C4 | 1.509 (4) |
O5—H4O | 0.79 (6) | C3—C4 | 1.498 (4) |
N1—H1N | 0.82 (4) | C4—H1 | 0.90 (3) |
H1O—O4—H2O | 112 (4) | N1—C1—C4 | 117.3 (2) |
H3O—O5—H4O | 108 (5) | O2—C2—N1 | 120.8 (2) |
H1N—N1—C1 | 118 (3) | O2—C2—N2 | 122.2 (3) |
H1N—N1—C2 | 117 (3) | N1—C2—N2 | 117.1 (2) |
C1—N1—C2 | 125.8 (2) | O3—C3—N2 | 119.4 (3) |
H2N—N2—C2 | 118 (3) | O3—C3—C4 | 123.1 (3) |
H2N—N2—C3 | 116 (3) | N2—C3—C4 | 117.5 (2) |
C2—N2—C3 | 126.0 (2) | C1—C4—C3 | 116.4 (2) |
O1—C1—N1 | 121.0 (3) | C1—C4—H1 | 103.9 (16) |
O1—C1—C4 | 121.7 (2) | C3—C4—H1 | 109.8 (16) |
C2—N1—C1—O1 | 180.000 (1) | C2—N2—C3—O3 | 180.000 (1) |
C2—N1—C1—C4 | 0.000 (1) | C2—N2—C3—C4 | 0.000 (2) |
C3—N2—C2—O2 | 180.000 (1) | O3—C3—C4—C1 | 180.000 (2) |
C3—N2—C2—N1 | 0.000 (1) | N2—C3—C4—C1 | 0.000 (1) |
C1—N1—C2—O2 | 180.000 (1) | O1—C1—C4—C3 | 180.000 (1) |
C1—N1—C2—N2 | 0.000 (1) | N1—C1—C4—C3 | 0.000 (1) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.83 (5) | 1.97 (5) | 2.767 (3) | 162 (5) |
O4—H2O···O1ii | 0.89 (5) | 1.98 (5) | 2.860 (3) | 170 (4) |
O5—H3O···O4 | 0.76 (6) | 1.98 (6) | 2.741 (4) | 179 (6) |
O5—H4O···O1 | 0.79 (6) | 2.02 (6) | 2.781 (3) | 164 (5) |
N1—H1N···O3iii | 0.82 (4) | 2.00 (4) | 2.818 (3) | 178 (4) |
N2—H2N···O5iv | 0.88 (4) | 1.84 (4) | 2.720 (3) | 172 (4) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.560 Mg m−3 |
Orthorhombic, Pmnb | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2bc 2a | Cell parameters from 4044 reflections |
a = 6.1665 (12) Å | θ = 2.3–28.3° |
b = 12.763 (2) Å | µ = 0.15 mm−1 |
c = 8.8814 (17) Å | T = 220 K |
V = 699.0 (2) Å3 | Block, colourless |
Z = 4 | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 923 independent reflections |
Radiation source: sealed tube | 824 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.043 |
thin–slice ω scans | θmax = 28.4°, θmin = 2.8° |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | h = −8→8 |
Tmin = 0.452, Tmax = 0.979 | k = −16→15 |
5578 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.045 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.124 | Only H-atom coordinates refined |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0685P)2 + 0.2425P] where P = (Fo2 + 2Fc2)/3 |
923 reflections | (Δ/σ)max < 0.001 |
82 parameters | Δρmax = 0.26 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C4H4N2O3·2H2O | V = 699.0 (2) Å3 |
Mr = 164.12 | Z = 4 |
Orthorhombic, Pmnb | Mo Kα radiation |
a = 6.1665 (12) Å | µ = 0.15 mm−1 |
b = 12.763 (2) Å | T = 220 K |
c = 8.8814 (17) Å | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 923 independent reflections |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | 824 reflections with I > 2σ(I) |
Tmin = 0.452, Tmax = 0.979 | Rint = 0.043 |
5578 measured reflections |
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.124 | Only H-atom coordinates refined |
S = 1.09 | Δρmax = 0.26 e Å−3 |
923 reflections | Δρmin = −0.28 e Å−3 |
82 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2500 | 0.55228 (10) | 0.47671 (15) | 0.0410 (5) | |
O2 | 0.2500 | 0.44186 (10) | 0.95839 (15) | 0.0383 (4) | |
O3 | 0.2500 | 0.79037 (10) | 0.88713 (17) | 0.0519 (6) | |
O4 | 0.2500 | 0.88645 (12) | 0.24042 (18) | 0.0454 (5) | |
H1O | 0.2500 | 0.917 (2) | 0.321 (4) | 0.055* | |
H2O | 0.2500 | 0.929 (3) | 0.168 (4) | 0.055* | |
O5 | 0.2500 | 0.67261 (13) | 0.21539 (17) | 0.0534 (6) | |
H3O | 0.2500 | 0.736 (3) | 0.220 (4) | 0.064* | |
H4O | 0.2500 | 0.648 (3) | 0.298 (4) | 0.064* | |
N1 | 0.2500 | 0.49880 (12) | 0.71729 (16) | 0.0282 (4) | |
H1N | 0.2500 | 0.438 (2) | 0.688 (3) | 0.034* | |
N2 | 0.2500 | 0.61723 (11) | 0.91948 (17) | 0.0270 (4) | |
H2N | 0.2500 | 0.631 (2) | 1.021 (3) | 0.032* | |
C1 | 0.2500 | 0.57491 (13) | 0.60995 (19) | 0.0259 (4) | |
C2 | 0.2500 | 0.51520 (13) | 0.8713 (2) | 0.0255 (4) | |
C3 | 0.2500 | 0.70406 (13) | 0.8297 (2) | 0.0290 (4) | |
C4 | 0.2500 | 0.68711 (13) | 0.6623 (2) | 0.0269 (4) | |
H1 | 0.127 (3) | 0.7160 (12) | 0.6216 (19) | 0.032* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0840 (12) | 0.0237 (7) | 0.0154 (7) | 0.000 | 0.000 | −0.0007 (5) |
O2 | 0.0794 (12) | 0.0158 (6) | 0.0197 (7) | 0.000 | 0.000 | 0.0050 (5) |
O3 | 0.1180 (17) | 0.0139 (7) | 0.0238 (8) | 0.000 | 0.000 | −0.0009 (5) |
O4 | 0.0928 (14) | 0.0224 (7) | 0.0210 (7) | 0.000 | 0.000 | −0.0014 (6) |
O5 | 0.1193 (18) | 0.0238 (7) | 0.0171 (7) | 0.000 | 0.000 | 0.0004 (5) |
N1 | 0.0562 (11) | 0.0117 (7) | 0.0168 (8) | 0.000 | 0.000 | −0.0011 (5) |
N2 | 0.0521 (10) | 0.0140 (7) | 0.0148 (7) | 0.000 | 0.000 | 0.0006 (5) |
C1 | 0.0441 (11) | 0.0162 (8) | 0.0172 (8) | 0.000 | 0.000 | 0.0009 (6) |
C2 | 0.0447 (11) | 0.0143 (8) | 0.0176 (8) | 0.000 | 0.000 | 0.0003 (6) |
C3 | 0.0536 (12) | 0.0133 (7) | 0.0203 (9) | 0.000 | 0.000 | 0.0015 (6) |
C4 | 0.0488 (12) | 0.0142 (7) | 0.0178 (8) | 0.000 | 0.000 | 0.0032 (6) |
O1—C1 | 1.218 (2) | N1—C2 | 1.383 (2) |
O2—C2 | 1.214 (2) | N1—H1N | 0.82 (3) |
O3—C3 | 1.214 (2) | N2—C3 | 1.365 (2) |
O4—H1O | 0.81 (3) | N2—C2 | 1.371 (2) |
O4—H2O | 0.85 (3) | N2—H2N | 0.92 (3) |
O5—H3O | 0.81 (4) | C1—C4 | 1.506 (2) |
O5—H4O | 0.80 (4) | C3—C4 | 1.502 (2) |
N1—C1 | 1.361 (2) | C4—H1 | 0.917 (17) |
H1O—O4—H2O | 111 (3) | N1—C1—C4 | 117.54 (15) |
H3O—O5—H4O | 110 (3) | O2—C2—N2 | 122.21 (17) |
C1—N1—C2 | 125.76 (15) | O2—C2—N1 | 120.88 (16) |
C1—N1—H1N | 117.2 (18) | N2—C2—N1 | 116.91 (15) |
C2—N1—H1N | 117.0 (18) | O3—C3—N2 | 119.42 (17) |
C3—N2—C2 | 126.06 (15) | O3—C3—C4 | 123.13 (16) |
C3—N2—H2N | 115.0 (16) | N2—C3—C4 | 117.45 (15) |
C2—N2—H2N | 119.0 (16) | C3—C4—C1 | 116.28 (14) |
O1—C1—N1 | 120.74 (16) | C3—C4—H1 | 109.4 (10) |
O1—C1—C4 | 121.71 (16) | C1—C4—H1 | 105.1 (10) |
C2—N1—C1—O1 | 180.0 | C2—N2—C3—O3 | 180.0 |
C2—N1—C1—C4 | 0.0 | C2—N2—C3—C4 | 0.000 (1) |
C3—N2—C2—O2 | 180.0 | O3—C3—C4—C1 | 180.0 |
C3—N2—C2—N1 | 0.0 | N2—C3—C4—C1 | 0.0 |
C1—N1—C2—O2 | 180.0 | O1—C1—C4—C3 | 180.0 |
C1—N1—C2—N2 | 0.0 | N1—C1—C4—C3 | 0.0 |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.81 (3) | 1.99 (3) | 2.767 (2) | 161 (3) |
O4—H2O···O1ii | 0.85 (3) | 2.03 (3) | 2.863 (2) | 170 (3) |
O5—H3O···O4 | 0.81 (4) | 1.93 (4) | 2.738 (2) | 178 (3) |
O5—H4O···O1 | 0.80 (4) | 2.00 (4) | 2.783 (2) | 166 (3) |
N1—H1N···O3iii | 0.82 (3) | 2.00 (3) | 2.817 (2) | 179 (2) |
N2—H2N···O5iv | 0.92 (3) | 1.80 (3) | 2.721 (2) | 173 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.558 Mg m−3 |
Orthorhombic, Pmnb | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2bc 2a | Cell parameters from 4267 reflections |
a = 6.1739 (4) Å | θ = 2.3–28.3° |
b = 12.7594 (9) Å | µ = 0.14 mm−1 |
c = 8.8831 (6) Å | T = 230 K |
V = 699.77 (8) Å3 | Block, colourless |
Z = 4 | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 923 independent reflections |
Radiation source: sealed tube | 859 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.023 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | h = −8→8 |
Tmin = 0.778, Tmax = 0.979 | k = −16→16 |
5804 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: using coordinates of another structure |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.043 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.112 | Only H-atom coordinates refined |
S = 1.14 | w = 1/[σ2(Fo2) + (0.0527P)2 + 0.2709P] where P = (Fo2 + 2Fc2)/3 |
923 reflections | (Δ/σ)max < 0.001 |
82 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
C4H4N2O3·2H2O | V = 699.77 (8) Å3 |
Mr = 164.12 | Z = 4 |
Orthorhombic, Pmnb | Mo Kα radiation |
a = 6.1739 (4) Å | µ = 0.14 mm−1 |
b = 12.7594 (9) Å | T = 230 K |
c = 8.8831 (6) Å | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 923 independent reflections |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | 859 reflections with I > 2σ(I) |
Tmin = 0.778, Tmax = 0.979 | Rint = 0.023 |
5804 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.112 | Only H-atom coordinates refined |
S = 1.14 | Δρmax = 0.35 e Å−3 |
923 reflections | Δρmin = −0.20 e Å−3 |
82 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2500 | 0.55230 (10) | 0.47675 (15) | 0.0434 (4) | |
O2 | 0.2500 | 0.44187 (10) | 0.95832 (15) | 0.0410 (4) | |
O3 | 0.2500 | 0.79043 (10) | 0.88707 (17) | 0.0536 (5) | |
O4 | 0.2500 | 0.88647 (12) | 0.24022 (18) | 0.0483 (5) | |
H1O | 0.2500 | 0.915 (2) | 0.320 (4) | 0.058* | |
H2O | 0.2500 | 0.930 (2) | 0.171 (3) | 0.058* | |
O5 | 0.2500 | 0.67255 (13) | 0.21533 (17) | 0.0564 (6) | |
H3O | 0.2500 | 0.737 (3) | 0.225 (4) | 0.068* | |
H4O | 0.2500 | 0.647 (3) | 0.299 (4) | 0.068* | |
N1 | 0.2500 | 0.49881 (11) | 0.71743 (16) | 0.0299 (4) | |
H1N | 0.2500 | 0.436 (2) | 0.689 (3) | 0.036* | |
N2 | 0.2500 | 0.61718 (11) | 0.91939 (16) | 0.0290 (4) | |
H2N | 0.2500 | 0.6304 (19) | 1.018 (3) | 0.035* | |
C1 | 0.2500 | 0.57501 (13) | 0.61023 (19) | 0.0273 (4) | |
C2 | 0.2500 | 0.51527 (13) | 0.87125 (19) | 0.0274 (4) | |
C3 | 0.2500 | 0.70409 (13) | 0.8297 (2) | 0.0305 (4) | |
C4 | 0.2500 | 0.68701 (13) | 0.6624 (2) | 0.0291 (4) | |
H1 | 0.128 (3) | 0.7175 (11) | 0.6207 (18) | 0.035* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0858 (12) | 0.0263 (7) | 0.0180 (6) | 0.000 | 0.000 | −0.0005 (5) |
O2 | 0.0812 (11) | 0.0192 (6) | 0.0225 (7) | 0.000 | 0.000 | 0.0046 (5) |
O3 | 0.1174 (16) | 0.0168 (6) | 0.0265 (7) | 0.000 | 0.000 | −0.0009 (5) |
O4 | 0.0949 (14) | 0.0263 (7) | 0.0238 (7) | 0.000 | 0.000 | −0.0016 (6) |
O5 | 0.1217 (18) | 0.0283 (7) | 0.0193 (7) | 0.000 | 0.000 | 0.0003 (6) |
N1 | 0.0558 (10) | 0.0138 (6) | 0.0201 (7) | 0.000 | 0.000 | −0.0014 (5) |
N2 | 0.0529 (10) | 0.0173 (7) | 0.0168 (7) | 0.000 | 0.000 | 0.0003 (5) |
C1 | 0.0432 (10) | 0.0194 (7) | 0.0194 (8) | 0.000 | 0.000 | 0.0011 (6) |
C2 | 0.0441 (10) | 0.0178 (8) | 0.0204 (8) | 0.000 | 0.000 | 0.0006 (6) |
C3 | 0.0522 (11) | 0.0167 (7) | 0.0225 (8) | 0.000 | 0.000 | 0.0015 (6) |
C4 | 0.0497 (11) | 0.0168 (7) | 0.0208 (8) | 0.000 | 0.000 | 0.0030 (6) |
O1—C1 | 1.221 (2) | N1—C1 | 1.361 (2) |
O2—C2 | 1.215 (2) | N1—C2 | 1.382 (2) |
O3—C3 | 1.214 (2) | N2—H2N | 0.89 (3) |
O4—H1O | 0.79 (3) | N2—C2 | 1.369 (2) |
O4—H2O | 0.83 (3) | N2—C3 | 1.366 (2) |
O5—H3O | 0.82 (4) | C1—C4 | 1.502 (2) |
O5—H4O | 0.82 (4) | C3—C4 | 1.502 (2) |
N1—H1N | 0.84 (3) | C4—H1 | 0.926 (16) |
H1O—O4—H2O | 111 (3) | N1—C1—C4 | 117.61 (15) |
H3O—O5—H4O | 108 (3) | O2—C2—N1 | 120.82 (16) |
H1N—N1—C1 | 118.2 (16) | O2—C2—N2 | 122.24 (16) |
H1N—N1—C2 | 116.1 (16) | N1—C2—N2 | 116.94 (15) |
C1—N1—C2 | 125.67 (15) | O3—C3—N2 | 119.48 (17) |
H2N—N2—C2 | 119.1 (16) | O3—C3—C4 | 123.18 (16) |
H2N—N2—C3 | 114.8 (16) | N2—C3—C4 | 117.35 (14) |
C2—N2—C3 | 126.10 (15) | C1—C4—C3 | 116.33 (14) |
O1—C1—N1 | 120.68 (16) | C1—C4—H1 | 106.0 (9) |
O1—C1—C4 | 121.71 (15) | C3—C4—H1 | 109.6 (10) |
C2—N1—C1—O1 | 180.0 | C2—N2—C3—O3 | 180.0 |
C2—N1—C1—C4 | 0.0 | C2—N2—C3—C4 | 0.000 (1) |
C3—N2—C2—O2 | 180.0 | O3—C3—C4—C1 | 180.0 |
C3—N2—C2—N1 | 0.0 | N2—C3—C4—C1 | 0.0 |
C1—N1—C2—O2 | 180.0 | O1—C1—C4—C3 | 180.0 |
C1—N1—C2—N2 | 0.0 | N1—C1—C4—C3 | 0.0 |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.79 (3) | 2.00 (3) | 2.770 (2) | 163 (3) |
O4—H2O···O1ii | 0.83 (3) | 2.04 (3) | 2.862 (2) | 171 (3) |
O5—H3O···O4 | 0.82 (4) | 1.92 (4) | 2.738 (2) | 178 (3) |
O5—H4O···O1 | 0.82 (4) | 1.99 (4) | 2.783 (2) | 166 (3) |
N1—H1N···O3iii | 0.84 (3) | 1.98 (3) | 2.816 (2) | 177 (2) |
N2—H2N···O5iv | 0.89 (3) | 1.84 (3) | 2.722 (2) | 174 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
C4H4N2O3·2H2O | F(000) = 344 |
Mr = 164.12 | Dx = 1.549 Mg m−3 |
Orthorhombic, Pmnb | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2bc 2a | Cell parameters from 3968 reflections |
a = 6.2144 (7) Å | θ = 2.2–28.2° |
b = 12.7512 (14) Å | µ = 0.14 mm−1 |
c = 8.8841 (10) Å | T = 270 K |
V = 703.99 (14) Å3 | Block, colourless |
Z = 4 | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 940 independent reflections |
Radiation source: sealed tube | 820 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.023 |
thin–slice ω scans | θmax = 28.3°, θmin = 2.8° |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | h = −8→8 |
Tmin = 0.797, Tmax = 0.979 | k = −16→16 |
5918 measured reflections | l = −11→11 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.041 | Only H-atom coordinates refined |
wR(F2) = 0.116 | w = 1/[σ2(Fo2) + (0.0639P)2 + 0.1693P] where P = (Fo2 + 2Fc2)/3 |
S = 1.11 | (Δ/σ)max < 0.001 |
940 reflections | Δρmax = 0.24 e Å−3 |
83 parameters | Δρmin = −0.29 e Å−3 |
0 restraints | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: using coordinates of another structure | Extinction coefficient: 0.040 (7) |
C4H4N2O3·2H2O | V = 703.99 (14) Å3 |
Mr = 164.12 | Z = 4 |
Orthorhombic, Pmnb | Mo Kα radiation |
a = 6.2144 (7) Å | µ = 0.14 mm−1 |
b = 12.7512 (14) Å | T = 270 K |
c = 8.8841 (10) Å | 0.53 × 0.42 × 0.15 mm |
Bruker SMART 1K CCD diffractometer | 940 independent reflections |
Absorption correction: multi-scan SADABS; Sheldrick (2003) | 820 reflections with I > 2σ(I) |
Tmin = 0.797, Tmax = 0.979 | Rint = 0.023 |
5918 measured reflections |
R[F2 > 2σ(F2)] = 0.041 | 0 restraints |
wR(F2) = 0.116 | Only H-atom coordinates refined |
S = 1.11 | Δρmax = 0.24 e Å−3 |
940 reflections | Δρmin = −0.29 e Å−3 |
83 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2500 | 0.55220 (10) | 0.47730 (15) | 0.0518 (5) | |
O2 | 0.2500 | 0.44201 (9) | 0.95826 (15) | 0.0484 (4) | |
O3 | 0.2500 | 0.79018 (10) | 0.88679 (16) | 0.0632 (6) | |
O4 | 0.2500 | 0.88616 (12) | 0.24031 (18) | 0.0582 (5) | |
H1O | 0.2500 | 0.916 (2) | 0.320 (4) | 0.070* | |
H2O | 0.2500 | 0.926 (2) | 0.174 (3) | 0.070* | |
O5 | 0.2500 | 0.67234 (13) | 0.21568 (16) | 0.0664 (6) | |
H3O | 0.2500 | 0.736 (3) | 0.224 (4) | 0.080* | |
H4O | 0.2500 | 0.646 (3) | 0.301 (4) | 0.080* | |
N1 | 0.2500 | 0.49881 (11) | 0.71776 (15) | 0.0358 (4) | |
H1N | 0.2500 | 0.437 (2) | 0.689 (3) | 0.043* | |
N2 | 0.2500 | 0.61715 (11) | 0.91930 (15) | 0.0343 (4) | |
H2N | 0.2500 | 0.6303 (19) | 1.018 (3) | 0.041* | |
C1 | 0.2500 | 0.57485 (13) | 0.61060 (18) | 0.0331 (4) | |
C2 | 0.2500 | 0.51514 (12) | 0.87106 (18) | 0.0325 (4) | |
C3 | 0.2500 | 0.70391 (12) | 0.8297 (2) | 0.0363 (4) | |
C4 | 0.2500 | 0.68682 (12) | 0.66246 (19) | 0.0348 (4) | |
H1 | 0.129 (3) | 0.7188 (11) | 0.6226 (17) | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.1011 (12) | 0.0322 (7) | 0.0221 (6) | 0.000 | 0.000 | −0.0012 (5) |
O2 | 0.0948 (12) | 0.0239 (6) | 0.0266 (7) | 0.000 | 0.000 | 0.0061 (5) |
O3 | 0.1365 (16) | 0.0208 (6) | 0.0323 (7) | 0.000 | 0.000 | −0.0010 (5) |
O4 | 0.1134 (14) | 0.0326 (7) | 0.0287 (7) | 0.000 | 0.000 | −0.0014 (5) |
O5 | 0.1405 (18) | 0.0348 (7) | 0.0239 (7) | 0.000 | 0.000 | 0.0004 (5) |
N1 | 0.0653 (10) | 0.0178 (6) | 0.0242 (7) | 0.000 | 0.000 | −0.0011 (5) |
N2 | 0.0616 (10) | 0.0211 (7) | 0.0201 (6) | 0.000 | 0.000 | 0.0004 (5) |
C1 | 0.0520 (10) | 0.0243 (7) | 0.0230 (8) | 0.000 | 0.000 | 0.0014 (6) |
C2 | 0.0516 (10) | 0.0216 (7) | 0.0242 (8) | 0.000 | 0.000 | 0.0014 (6) |
C3 | 0.0621 (11) | 0.0195 (7) | 0.0274 (8) | 0.000 | 0.000 | 0.0015 (6) |
C4 | 0.0588 (11) | 0.0203 (7) | 0.0252 (8) | 0.000 | 0.000 | 0.0039 (6) |
O1—C1 | 1.219 (2) | N1—C1 | 1.359 (2) |
O2—C2 | 1.212 (2) | N1—C2 | 1.378 (2) |
O3—C3 | 1.211 (2) | N2—H2N | 0.90 (2) |
O4—H1O | 0.80 (3) | N2—C2 | 1.369 (2) |
O4—H2O | 0.78 (3) | N2—C3 | 1.363 (2) |
O5—H3O | 0.82 (4) | C1—C4 | 1.500 (2) |
O5—H4O | 0.83 (4) | C3—C4 | 1.502 (2) |
N1—H1N | 0.83 (3) | C4—H1 | 0.927 (15) |
H1O—O4—H2O | 111 (3) | N1—C1—C4 | 117.64 (14) |
H3O—O5—H4O | 109 (3) | O2—C2—N1 | 121.02 (15) |
H1N—N1—C1 | 117.6 (16) | O2—C2—N2 | 122.04 (16) |
H1N—N1—C2 | 116.6 (16) | N1—C2—N2 | 116.93 (14) |
C1—N1—C2 | 125.78 (14) | O3—C3—N2 | 119.52 (16) |
H2N—N2—C2 | 119.0 (15) | O3—C3—C4 | 123.09 (15) |
H2N—N2—C3 | 114.9 (15) | N2—C3—C4 | 117.39 (14) |
C2—N2—C3 | 126.03 (14) | C1—C4—C3 | 116.23 (13) |
O1—C1—N1 | 120.77 (16) | C1—C4—H1 | 107.5 (9) |
O1—C1—C4 | 121.59 (15) | C3—C4—H1 | 108.3 (9) |
C2—N1—C1—O1 | 180.0 | C2—N2—C3—O3 | 180.0 |
C2—N1—C1—C4 | 0.0 | C2—N2—C3—C4 | 0.0 |
C3—N2—C2—O2 | 180.0 | O1—C1—C4—C3 | 180.0 |
C3—N2—C2—N1 | 0.0 | N1—C1—C4—C3 | 0.0 |
C1—N1—C2—O2 | 180.0 | O3—C3—C4—C1 | 180.0 |
C1—N1—C2—N2 | 0.0 | N2—C3—C4—C1 | 0.0 |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.80 (3) | 2.00 (3) | 2.771 (2) | 162 (3) |
O4—H2O···O1ii | 0.78 (3) | 2.09 (3) | 2.867 (2) | 171 (3) |
O5—H3O···O4 | 0.82 (4) | 1.92 (4) | 2.735 (2) | 179 (3) |
O5—H4O···O1 | 0.83 (4) | 1.97 (4) | 2.784 (2) | 167 (3) |
N1—H1N···O3iii | 0.83 (3) | 1.99 (3) | 2.818 (2) | 178 (2) |
N2—H2N···O5iv | 0.90 (2) | 1.83 (3) | 2.725 (2) | 174 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
Experimental details
(100) | (150) | (170) | (190) | |
Crystal data | ||||
Chemical formula | C4H4N2O3·2H2O | C4H4N2O3·2H2O | C4H4N2O3·2H2O | C4H4N2O3·2H2O |
Mr | 164.12 | 164.12 | 164.12 | 164.12 |
Crystal system, space group | Monoclinic, P21/n | Monoclinic, P21/n | Monoclinic, P21/n | Monoclinic, P21/n |
Temperature (K) | 100 | 150 | 170 | 190 |
a, b, c (Å) | 6.0970 (5), 12.7152 (10), 8.8587 (7) | 6.1130 (8), 12.7149 (16), 8.8564 (11) | 6.1270 (5), 12.7253 (11), 8.8633 (8) | 6.1377 (5), 12.7306 (11), 8.8641 (8) |
α, β, γ (°) | 90, 94.0510 (14), 90 | 90, 93.437 (2), 90 | 90, 93.0680 (16), 90 | 90, 92.5280 (15), 90 |
V (Å3) | 685.05 (9) | 687.14 (15) | 690.06 (10) | 691.94 (10) |
Z | 4 | 4 | 4 | 4 |
Radiation type | Mo Kα | Mo Kα | Mo Kα | Mo Kα |
µ (mm−1) | 0.15 | 0.15 | 0.15 | 0.15 |
Crystal size (mm) | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 |
Data collection | ||||
Diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer |
Absorption correction | Multi-scan TWINABS; (Sheldrick, 2002) | Multi-scan TWINABS; Sheldrick (2002) | Multi-scan TWINABS; Sheldrick (2002) | Multi-scan TWINABS; Sheldrick (2002) |
Tmin, Tmax | 0.861, 0.978 | 0.861, 0.978 | 0.823, 0.978 | 0.782, 0.978 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9480, 2263, 2126 | 8078, 2212, 2148 | 9428, 2124, 2011 | 9902, 2140, 1930 |
Rint | 0.019 | 0.029 | 0.024 | 0.024 |
(sin θ/λ)max (Å−1) | 0.666 | 0.666 | 0.668 | 0.667 |
Refinement | ||||
R[F2 > 2σ(F2)], wR(F2), S | 0.032, 0.085, 1.11 | 0.051, 0.132, 1.26 | 0.040, 0.105, 1.16 | 0.037, 0.105, 1.06 |
No. of reflections | 2263 | 2212 | 2124 | 2140 |
No. of parameters | 120 | 120 | 120 | 120 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.32, −0.30 | 0.38, −0.34 | 0.30, −0.33 | 0.26, −0.28 |
(200) | (210) | (215) | (216) | |
Crystal data | ||||
Chemical formula | C4H4N2O3·2H2O | C4H4N2O3·2H2O | C4H4N2O3·2H2O | C4H4N2O3·2H2O |
Mr | 164.12 | 164.12 | 164.12 | 164.12 |
Crystal system, space group | Monoclinic, P21/n | Monoclinic, P21/n | Monoclinic, P21/n | Monoclinic, P21/n |
Temperature (K) | 200 | 210 | 215 | 216 |
a, b, c (Å) | 6.1313 (12), 12.703 (2), 8.8456 (17) | 6.1538 (15), 12.747 (3), 8.877 (2) | 6.1580 (9), 12.7515 (18), 8.8763 (13) | 6.1567 (16), 12.733 (3), 8.865 (2) |
α, β, γ (°) | 90, 92.187 (4), 90 | 90, 91.627 (4), 90 | 90, 91.263 (3), 90 | 90, 91.180 (5), 90 |
V (Å3) | 688.5 (2) | 696.0 (3) | 696.83 (17) | 694.8 (3) |
Z | 4 | 4 | 4 | 4 |
Radiation type | Mo Kα | Mo Kα | Mo Kα | Mo Kα |
µ (mm−1) | 0.15 | 0.15 | 0.15 | 0.15 |
Crystal size (mm) | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 |
Data collection | ||||
Diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer |
Absorption correction | Multi-scan TWINABS; Sheldrick (2002) | Multi-scan TWINABS; Sheldrick (2002) | Multi-scan TWINABS; Sheldrick (2002) | Multi-scan TWINABS; Sheldrick (2002) |
Tmin, Tmax | 0.553, 0.978 | 0.574, 0.979 | 0.331, 0.979 | 0.492, 0.979 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7874, 2456, 2397 | 7495, 2165, 2018 | 8726, 2442, 2299 | 7321, 2209, 2058 |
Rint | 0.029 | 0.027 | 0.026 | 0.024 |
(sin θ/λ)max (Å−1) | 0.666 | 0.667 | 0.667 | 0.677 |
Refinement | ||||
R[F2 > 2σ(F2)], wR(F2), S | 0.087, 0.197, 1.31 | 0.066, 0.152, 1.28 | 0.069, 0.194, 1.19 | 0.068, 0.181, 1.30 |
No. of reflections | 2456 | 2165 | 2442 | 2209 |
No. of parameters | 120 | 120 | 120 | 120 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.50, −0.58 | 0.42, −0.42 | 0.41, −0.44 | 0.33, −0.47 |
(217) | (218) | (219) | (220) | |
Crystal data | ||||
Chemical formula | C4H4N2O3·2H2O | C4H4N2O3·2H2O | C4H4N2O3·2H2O | C4H4N2O3·2H2O |
Mr | 164.12 | 164.12 | 164.12 | 164.12 |
Crystal system, space group | Orthorhombic, Pmnb | Orthorhombic, Pmnb | Orthorhombic, Pmnb | Orthorhombic, Pmnb |
Temperature (K) | 217 | 218 | 219 | 220 |
a, b, c (Å) | 6.1770 (18), 12.785 (4), 8.898 (3) | 6.1626 (19), 12.757 (4), 8.876 (3) | 6.1624 (15), 12.757 (3), 8.878 (2) | 6.1665 (12), 12.763 (2), 8.8814 (17) |
α, β, γ (°) | 90, 90, 90 | 90, 90, 90 | 90, 90, 90 | 90, 90, 90 |
V (Å3) | 702.7 (3) | 697.8 (4) | 697.9 (3) | 699.0 (2) |
Z | 4 | 4 | 4 | 4 |
Radiation type | Mo Kα | Mo Kα | Mo Kα | Mo Kα |
µ (mm−1) | 0.14 | 0.15 | 0.15 | 0.15 |
Crystal size (mm) | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 |
Data collection | ||||
Diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer |
Absorption correction | Multi-scan SADABS; Sheldrick (2003) | Multi-scan SADABS; Sheldrick (2003) | Multi-scan SADBAS; Sheldrick (2003) | Multi-scan SADABS; Sheldrick (2003) |
Tmin, Tmax | 0.321, 0.979 | 0.351, 0.979 | 0.353, 0.979 | 0.452, 0.979 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5924, 889, 800 | 5224, 904, 829 | 5236, 914, 865 | 5578, 923, 824 |
Rint | 0.050 | 0.047 | 0.046 | 0.043 |
(sin θ/λ)max (Å−1) | 0.669 | 0.666 | 0.667 | 0.669 |
Refinement | ||||
R[F2 > 2σ(F2)], wR(F2), S | 0.061, 0.154, 1.25 | 0.054, 0.137, 1.17 | 0.066, 0.158, 1.32 | 0.045, 0.124, 1.09 |
No. of reflections | 889 | 904 | 914 | 923 |
No. of parameters | 82 | 82 | 82 | 82 |
H-atom treatment | Only H-atom coordinates refined | Only H-atom coordinates refined | Only H-atom coordinates refined | Only H-atom coordinates refined |
Δρmax, Δρmin (e Å−3) | 0.35, −0.28 | 0.29, −0.28 | 0.32, −0.33 | 0.26, −0.28 |
(230) | (270) | |
Crystal data | ||
Chemical formula | C4H4N2O3·2H2O | C4H4N2O3·2H2O |
Mr | 164.12 | 164.12 |
Crystal system, space group | Orthorhombic, Pmnb | Orthorhombic, Pmnb |
Temperature (K) | 230 | 270 |
a, b, c (Å) | 6.1739 (4), 12.7594 (9), 8.8831 (6) | 6.2144 (7), 12.7512 (14), 8.8841 (10) |
α, β, γ (°) | 90, 90, 90 | 90, 90, 90 |
V (Å3) | 699.77 (8) | 703.99 (14) |
Z | 4 | 4 |
Radiation type | Mo Kα | Mo Kα |
µ (mm−1) | 0.14 | 0.14 |
Crystal size (mm) | 0.53 × 0.42 × 0.15 | 0.53 × 0.42 × 0.15 |
Data collection | ||
Diffractometer | Bruker SMART 1K CCD diffractometer | Bruker SMART 1K CCD diffractometer |
Absorption correction | Multi-scan SADABS; Sheldrick (2003) | Multi-scan SADABS; Sheldrick (2003) |
Tmin, Tmax | 0.778, 0.979 | 0.797, 0.979 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5804, 923, 859 | 5918, 940, 820 |
Rint | 0.023 | 0.023 |
(sin θ/λ)max (Å−1) | 0.667 | 0.667 |
Refinement | ||
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.112, 1.14 | 0.041, 0.116, 1.11 |
No. of reflections | 923 | 940 |
No. of parameters | 82 | 83 |
H-atom treatment | Only H-atom coordinates refined | Only H-atom coordinates refined |
Δρmax, Δρmin (e Å−3) | 0.35, −0.20 | 0.24, −0.29 |
Computer programs: Bruker SMART, Bruker SAINT, SHELXS97 (Sheldrick, 1990), by using coordinates of another structure, using coordinates of 150K structure, SHELXL97 (Sheldrick, 1997), Bruker SHELXTL and local programs.
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.819 (17) | 1.969 (17) | 2.7583 (11) | 161.9 (16) |
O4—H2O···O1ii | 0.822 (17) | 2.034 (17) | 2.8508 (11) | 172.4 (15) |
O5—H3O···O4 | 0.821 (18) | 1.931 (19) | 2.7463 (12) | 171.7 (17) |
O5—H4O···O1 | 0.828 (17) | 1.967 (18) | 2.7819 (12) | 167.9 (16) |
N1—H1N···O3iii | 0.823 (15) | 1.986 (16) | 2.8084 (12) | 177.2 (14) |
N2—H2N···O5iv | 0.874 (15) | 1.861 (15) | 2.7277 (12) | 171.2 (14) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.81 (3) | 1.98 (3) | 2.759 (2) | 161 (3) |
O4—H2O···O1ii | 0.83 (3) | 2.03 (3) | 2.850 (2) | 171 (3) |
O5—H3O···O4 | 0.79 (3) | 1.96 (3) | 2.743 (2) | 173 (4) |
O5—H4O···O1 | 0.81 (3) | 1.99 (3) | 2.781 (2) | 165 (3) |
N1—H1N···O3iii | 0.82 (3) | 2.00 (3) | 2.814 (2) | 175 (3) |
N2—H2N···O5iv | 0.85 (3) | 1.88 (3) | 2.721 (2) | 173 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.83 (2) | 1.97 (2) | 2.7611 (14) | 161 (2) |
O4—H2O···O1ii | 0.82 (2) | 2.04 (2) | 2.8546 (14) | 171 (2) |
O5—H3O···O4 | 0.83 (2) | 1.91 (2) | 2.7397 (16) | 174 (2) |
O5—H4O···O1 | 0.82 (2) | 1.97 (2) | 2.7797 (15) | 167 (2) |
N1—H1N···O3iii | 0.838 (18) | 1.975 (18) | 2.8117 (15) | 176.5 (16) |
N2—H2N···O5iv | 0.858 (18) | 1.870 (18) | 2.7224 (14) | 172.3 (17) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.852 (18) | 1.941 (19) | 2.7606 (13) | 161.1 (17) |
O4—H2O···O1ii | 0.827 (19) | 2.037 (19) | 2.8567 (12) | 170.7 (17) |
O5—H3O···O4 | 0.82 (2) | 1.92 (2) | 2.7384 (14) | 175 (2) |
O5—H4O···O1 | 0.84 (2) | 1.96 (2) | 2.7785 (13) | 167.3 (18) |
N1—H1N···O3iii | 0.835 (16) | 1.976 (16) | 2.8103 (13) | 176.8 (14) |
N2—H2N···O5iv | 0.870 (16) | 1.854 (16) | 2.7204 (13) | 173.7 (15) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.85 (5) | 1.96 (5) | 2.755 (3) | 155 (4) |
O4—H2O···O1ii | 0.80 (5) | 2.05 (5) | 2.848 (3) | 173 (5) |
O5—H3O···O4 | 0.78 (5) | 1.96 (5) | 2.733 (3) | 170 (6) |
O5—H4O···O1 | 0.79 (5) | 2.00 (5) | 2.772 (3) | 165 (5) |
N1—H1N···O3iii | 0.80 (4) | 2.01 (4) | 2.813 (3) | 175 (4) |
N2—H2N···O5iv | 0.85 (4) | 1.87 (4) | 2.714 (3) | 174 (4) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.81 (4) | 2.00 (4) | 2.767 (3) | 157 (3) |
O4—H2O···O1ii | 0.83 (4) | 2.04 (4) | 2.861 (3) | 169 (4) |
O5—H3O···O4 | 0.80 (4) | 1.94 (4) | 2.739 (3) | 174 (5) |
O5—H4O···O1 | 0.79 (4) | 2.01 (4) | 2.782 (3) | 166 (4) |
N1—H1N···O3iii | 0.84 (3) | 1.98 (3) | 2.815 (3) | 176 (3) |
N2—H2N···O5iv | 0.83 (3) | 1.90 (3) | 2.724 (3) | 173 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.86 (4) | 1.95 (4) | 2.763 (2) | 159 (3) |
O4—H2O···O1ii | 0.85 (4) | 2.02 (4) | 2.860 (2) | 169 (3) |
O5—H3O···O4 | 0.83 (4) | 1.91 (4) | 2.740 (3) | 179 (4) |
O5—H4O···O1 | 0.82 (4) | 1.98 (4) | 2.778 (2) | 166 (4) |
N1—H1N···O3iii | 0.83 (3) | 1.99 (3) | 2.816 (2) | 177 (3) |
N2—H2N···O5iv | 0.83 (3) | 1.89 (3) | 2.722 (2) | 173 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.85 (4) | 1.95 (4) | 2.763 (3) | 161 (3) |
O4—H2O···O1ii | 0.83 (4) | 2.05 (4) | 2.854 (3) | 163 (4) |
O5—H3O···O4 | 0.78 (4) | 1.98 (4) | 2.735 (3) | 165 (5) |
O5—H4O···O1 | 0.82 (4) | 1.98 (4) | 2.775 (3) | 160 (4) |
N1—H1N···O3iii | 0.81 (3) | 2.01 (3) | 2.815 (3) | 176 (4) |
N2—H2N···O5iv | 0.87 (3) | 1.86 (3) | 2.719 (3) | 170 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.84 (5) | 1.95 (5) | 2.771 (3) | 166 (4) |
O4—H2O···O1ii | 0.83 (5) | 2.05 (5) | 2.867 (3) | 169 (4) |
O5—H3O···O4 | 0.82 (5) | 1.92 (6) | 2.744 (3) | 178 (5) |
O5—H4O···O1 | 0.77 (5) | 2.04 (5) | 2.788 (3) | 163 (5) |
N1—H1N···O3iii | 0.81 (4) | 2.01 (4) | 2.824 (3) | 178 (3) |
N2—H2N···O5iv | 0.92 (4) | 1.81 (4) | 2.726 (3) | 172 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.83 (4) | 1.96 (4) | 2.764 (3) | 162 (4) |
O4—H2O···O1ii | 0.85 (4) | 2.03 (4) | 2.861 (3) | 168 (4) |
O5—H3O···O4 | 0.80 (5) | 1.94 (5) | 2.738 (3) | 179 (4) |
O5—H4O···O1 | 0.79 (4) | 2.01 (5) | 2.780 (3) | 166 (4) |
N1—H1N···O3iii | 0.82 (3) | 2.00 (3) | 2.817 (3) | 178 (3) |
N2—H2N···O5iv | 0.92 (3) | 1.81 (3) | 2.720 (3) | 171 (3) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.83 (5) | 1.97 (5) | 2.767 (3) | 162 (5) |
O4—H2O···O1ii | 0.89 (5) | 1.98 (5) | 2.860 (3) | 170 (4) |
O5—H3O···O4 | 0.76 (6) | 1.98 (6) | 2.741 (4) | 179 (6) |
O5—H4O···O1 | 0.79 (6) | 2.02 (6) | 2.781 (3) | 164 (5) |
N1—H1N···O3iii | 0.82 (4) | 2.00 (4) | 2.818 (3) | 178 (4) |
N2—H2N···O5iv | 0.88 (4) | 1.84 (4) | 2.720 (3) | 172 (4) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.81 (3) | 1.99 (3) | 2.767 (2) | 161 (3) |
O4—H2O···O1ii | 0.85 (3) | 2.03 (3) | 2.863 (2) | 170 (3) |
O5—H3O···O4 | 0.81 (4) | 1.93 (4) | 2.738 (2) | 178 (3) |
O5—H4O···O1 | 0.80 (4) | 2.00 (4) | 2.783 (2) | 166 (3) |
N1—H1N···O3iii | 0.82 (3) | 2.00 (3) | 2.817 (2) | 179 (2) |
N2—H2N···O5iv | 0.92 (3) | 1.80 (3) | 2.721 (2) | 173 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.79 (3) | 2.00 (3) | 2.770 (2) | 163 (3) |
O4—H2O···O1ii | 0.83 (3) | 2.04 (3) | 2.862 (2) | 171 (3) |
O5—H3O···O4 | 0.82 (4) | 1.92 (4) | 2.738 (2) | 178 (3) |
O5—H4O···O1 | 0.82 (4) | 1.99 (4) | 2.783 (2) | 166 (3) |
N1—H1N···O3iii | 0.84 (3) | 1.98 (3) | 2.816 (2) | 177 (2) |
N2—H2N···O5iv | 0.89 (3) | 1.84 (3) | 2.722 (2) | 174 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1O···O2i | 0.80 (3) | 2.00 (3) | 2.771 (2) | 162 (3) |
O4—H2O···O1ii | 0.78 (3) | 2.09 (3) | 2.867 (2) | 171 (3) |
O5—H3O···O4 | 0.82 (4) | 1.92 (4) | 2.735 (2) | 179 (3) |
O5—H4O···O1 | 0.83 (4) | 1.97 (4) | 2.784 (2) | 167 (3) |
N1—H1N···O3iii | 0.83 (3) | 1.99 (3) | 2.818 (2) | 178 (2) |
N2—H2N···O5iv | 0.90 (2) | 1.83 (3) | 2.725 (2) | 174 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) x, y, z+1. |
Acknowledgements
We thank Dr Neil Brooks and Dr Ross Harrington, Newcastle University, for advice related to
and for experimental assistance, the EPSRC for financial support, and Professor Sally Price, University College London, for helpful discussions and pre-publication results relating to polymorph prediction for barbituric acid.References
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