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2-Amino­pyridinium di­phenyl­phosphinate monohydrate

aSchool of Chemistry, University College of Science, University of Tehran, Tehran, Iran, and bPlasma Physics Research Center, Science & Reseach Campus, Islamic Azad University, Tehran, Iran
*Correspondence e-mail: aabbasi@khayam.ut.ac.ir

(Received 3 August 2009; accepted 24 August 2009; online 29 August 2009)

In the crystal of the title hydrated salt, C5H7N2+·C12H10O2P·H2O, the cations, anions and water mol­ecules connected by N—H⋯O and O—H⋯O hydrogen bonds into a layer along the bc plane; the phenyl rings protrude into the space between the layers. The dihedral angle between rings of anion is 86.1 (1)°.

Related literature

For bidentate ligands with both hard (nitrogen) and soft (phosphorous) donors, see: Espinet & Soulantica (1999[Espinet, P. & Soulantica, J. K. (1999). Coord. Chem. Rev. 193, 499-556.]); Jeffrey & Rauchfuss (1979[Jeffrey, J. C. & Rauchfuss, T. B. (1979). Inorg. Chem. 18, 2658-2666.]). For the use of diphenyl­phosphinic acid in the extraction of trivalent lanthanide cations and as a flame retardant in the ep­oxy resins used in printed circuit boards, see: Almeida (1974[Almeida, I. G. D. (1974). J. Radioanal. Chem. 22, 21-28.]); von Gentzkow et al. (1996[Gentzkow, W. von, Huber, J. & Kapitza, H. (1996). US Patent No. 5 587 243.]); Huber et al. (1998[Huber, J., Kapitza, H. & Kleiner, H.-J. (1998). US Patent No. 5 811 188.]).

[Scheme 1]

Experimental

Crystal data
  • C5H7N2+·C12H10O2P·H2O

  • Mr = 330.31

  • Monoclinic, P 21 /c

  • a = 15.2716 (19) Å

  • b = 9.979 (2) Å

  • c = 11.7671 (15) Å

  • β = 103.073 (10)°

  • V = 1746.8 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.17 mm−1

  • T = 295 K

  • 0.60 × 0.35 × 0.21 mm

Data collection
  • Stoe IPDS-II diffractometer

  • Absorption correction: analytical (X-SHAPE; Stoe & Cie, 2007[Stoe & Cie (2007). X-AREA, X-RED and X-SHAPE. Stoe & Cie GmbH, Darmstadt, Germany.]) Tmin = 0.813, Tmax = 0.965

  • 8165 measured reflections

  • 2972 independent reflections

  • 1660 reflections with I > 2σ(I)

  • Rint = 0.097

Refinement
  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.130

  • S = 1.02

  • 2972 reflections

  • 214 parameters

  • 3 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O1 0.86 1.80 2.655 (4) 175
N2—H13⋯O2 0.86 2.02 2.881 (4) 176
N2—H14⋯O3i 0.86 2.04 2.853 (4) 157
O3—H3A⋯O2ii 0.95 (2) 1.79 (2) 2.743 (3) 175 (3)
O3—H3B⋯O1 0.95 (2) 1.80 (2) 2.744 (3) 171 (3)
Symmetry codes: (i) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: X-RED (Stoe & Cie, 2007[Stoe & Cie (2007). X-AREA, X-RED and X-SHAPE. Stoe & Cie GmbH, Darmstadt, Germany.]); cell refinement: X-AREA (Stoe & Cie, 2007[Stoe & Cie (2007). X-AREA, X-RED and X-SHAPE. Stoe & Cie GmbH, Darmstadt, Germany.]); data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 2001[Brandenburg, K. (2001). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Bidentate ligands containing both hard (nitrogen) and soft (phosphorous) donor atoms are extremely fruitful in both homogenous catalysis and coordination chemistry (Espinet & Soulantica, 1999). Because of having both hard and soft donor atoms, they are called hemilabile ligands (Jeffrey & Rauchfuss, 1979). Diphenylphosphinic acid and its derivatives have been widely used because of their variety of applications. It has been extensively used for extraction of trivalent lanthanide cations and as a flame retardant in epoxy resins that are used in printed circuit boards (Almeida, 1974; Huber, et al., 1998; von Gentzkow, et al., 1996).

The molecular structure of (I) and the atom-numbering scheme are shown in Fig. 1. In this work, attempting to get a new hemilabile bidentate ligand, we obtained pyridinium-2-amine di(phenyl)phosphinate monohydrate, which was unexpectedly produced due to the breaking of P—N bond, probably due to its sensitivity to air and humidity. In the crystal structure, there are three discrete moieties in the asymmetric unit (phosphinic acid, pyridine ring and one water molecule) that are in contact by several hydogen bonds, making a well defined motif. There are also C—H···π interactions between phophinate and pyridinium groups between neighboring motifs. Two P—O bonds are slightly different in distances, (P1—O1 = 1.507 Å and P1—O2 = 1.498 Å), that can be due to the hydrogen bonds between the nitrogen atoms of pyridinium rings to the phosphinate molecules (N1—H1A···O1 and N2—H13···O2, 2.655 (4) and 2.881 (4) Å, respectively, see Table 1). The motifs are in contact by hydrogen bonds in bc plane, making sheets in which these sheets are held together by van der Waals interactions (see Fig. 2 & 3).

Related literature top

For hemilabile ligands, see: Espinet & Soulantica (1999); Jeffrey & Rauchfuss (1979). Diphenylphosphinic acid has been extensively used in the extraction of trivalent lanthanide cations and as a flame retardant in the epoxy resins used in printed circuit boards, see: Almeida (1974); von Gentzkow et al. (1996); Huber et al. (1998).

Experimental top

Synthesis was carried out under argon atmosphere at 0°C, by dropwise addition of neat chlorodiphenylphosphine (3.32 g, 15.04 mmol) to a THF solution of 2-aminopyridine (1.41 g, 15.04 mmol) and triethylamine (1.568 g, 15.5 mmol). The mixture was warmed slowly to room temperature, followed by 24 h stirring. Triethylamine hydrochloride precipitates were then filtered off. Removing the excess solvent under reduced pressure, leads to a pale yellow oily product, that was solidifies by solving in benzene and stored in fridge. The obtained solid (0.100 g, 0.359 mmol) together with stoichiometric quantity of sulfur (0.011 g, 0.359 mmol) in toluene were refluxed for 30 minutes and the resulting solution was dried. Recrystallizing in hot toluene afforded colorless needle crystals.

Refinement top

All H atoms (except water molecule) were positioned geometrically [C—H = 0.93Å and N—H = 0.86 (1)Å] and refined using a riding model, with Uiso(H)=1.2Ueq(C & N). The H atoms for the water molecules were located from electron density map and refined with a tight restraint of the O-H bond length of 0.95 (2) Å, while keeping the H···H distance at a value corresponding to the H-O-H angle 104o.

Computing details top

Data collection: X-RED (Stoe & Cie, 2007); cell refinement: X-AREA (Stoe & Cie, 2007); data reduction: X-AREA (Stoe & Cie, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I), with 50% probability displacement ellipsoids. H atoms are shown as circles of arbitrary radii.
[Figure 2] Fig. 2. A packing diagram of (I). Hydrogen bonds are shown as dashed lines.
2-Aminopyridinium diphenylphosphinate monohydrate top
Crystal data top
C5H7N2+·C12H10O2P·H2OF(000) = 696
Mr = 330.31Dx = 1.256 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8165 reflections
a = 15.2716 (19) Åθ = 2.5–25.0°
b = 9.979 (2) ŵ = 0.17 mm1
c = 11.7671 (15) ÅT = 295 K
β = 103.073 (10)°Needle, colorless
V = 1746.8 (5) Å30.60 × 0.35 × 0.21 mm
Z = 4
Data collection top
Stoe IPDS-II
diffractometer
2972 independent reflections
Radiation source: fine-focus sealed tube1660 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.097
ϕ oscillation scansθmax = 25.0°, θmin = 2.5°
Absorption correction: analytical
(X-SHAPE; Stoe & Cie, 2007)
h = 1817
Tmin = 0.813, Tmax = 0.965k = 1111
8165 measured reflectionsl = 1313
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.02 w = 1/[σ2(Fo2) + (0.05P)2]
where P = (Fo2 + 2Fc2)/3
2972 reflections(Δ/σ)max < 0.001
214 parametersΔρmax = 0.21 e Å3
3 restraintsΔρmin = 0.20 e Å3
Crystal data top
C5H7N2+·C12H10O2P·H2OV = 1746.8 (5) Å3
Mr = 330.31Z = 4
Monoclinic, P21/cMo Kα radiation
a = 15.2716 (19) ŵ = 0.17 mm1
b = 9.979 (2) ÅT = 295 K
c = 11.7671 (15) Å0.60 × 0.35 × 0.21 mm
β = 103.073 (10)°
Data collection top
Stoe IPDS-II
diffractometer
2972 independent reflections
Absorption correction: analytical
(X-SHAPE; Stoe & Cie, 2007)
1660 reflections with I > 2σ(I)
Tmin = 0.813, Tmax = 0.965Rint = 0.097
8165 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0543 restraints
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 0.21 e Å3
2972 reflectionsΔρmin = 0.20 e Å3
214 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
P10.23381 (6)0.38907 (9)0.28738 (7)0.0566 (3)
O10.19470 (14)0.3089 (2)0.37261 (18)0.0684 (6)
O20.16905 (13)0.4311 (2)0.17762 (16)0.0679 (6)
C10.2857 (2)0.5359 (3)0.3623 (3)0.0549 (8)
C20.3479 (2)0.5264 (4)0.4676 (3)0.0719 (10)
H50.36560.44190.49750.086*
C30.3843 (3)0.6372 (4)0.5292 (3)0.0856 (11)
H40.42620.62790.59970.103*
C40.3587 (3)0.7608 (5)0.4863 (4)0.0922 (12)
H30.38290.83670.52750.111*
C50.2982 (3)0.7738 (4)0.3836 (4)0.1035 (14)
H20.28050.85890.35520.124*
C60.2622 (3)0.6628 (4)0.3205 (3)0.0831 (11)
H10.22170.67360.24910.100*
C70.3262 (2)0.2968 (3)0.2542 (3)0.0544 (8)
C80.3694 (2)0.3417 (3)0.1706 (3)0.0674 (9)
H100.34870.41820.12780.081*
C90.4430 (2)0.2742 (4)0.1497 (3)0.0769 (10)
H90.47150.30620.09330.092*
C100.4746 (2)0.1605 (4)0.2111 (4)0.0815 (11)
H80.52470.11590.19740.098*
C110.4311 (3)0.1143 (4)0.2928 (3)0.0859 (11)
H70.45140.03670.33430.103*
C120.3575 (2)0.1808 (3)0.3147 (3)0.0728 (10)
H60.32870.14770.37050.087*
N10.02673 (18)0.3481 (3)0.3918 (2)0.0648 (7)
H1A0.08010.33700.38110.078*
N20.00790 (19)0.4687 (3)0.2200 (2)0.0800 (9)
H130.04560.45580.21050.096*
H140.04580.51420.16950.096*
C130.0324 (2)0.4193 (3)0.3131 (3)0.0638 (9)
C140.1181 (2)0.4384 (4)0.3339 (3)0.0765 (10)
H180.16050.48880.28220.092*
C150.1392 (3)0.3836 (4)0.4294 (4)0.0877 (12)
H170.19630.39650.44300.105*
C160.0765 (3)0.3082 (4)0.5071 (4)0.0874 (12)
H160.09140.26900.57190.105*
C170.0058 (3)0.2930 (4)0.4874 (3)0.0789 (10)
H150.04890.24420.53970.095*
O30.16544 (17)0.0543 (2)0.44385 (19)0.0746 (7)
H3A0.163 (2)0.059 (3)0.5239 (12)0.090*
H3B0.181 (2)0.1430 (16)0.426 (3)0.090*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.0523 (5)0.0634 (6)0.0563 (5)0.0041 (4)0.0170 (4)0.0055 (4)
O10.0624 (14)0.0753 (15)0.0752 (13)0.0004 (11)0.0318 (12)0.0181 (12)
O20.0537 (13)0.0925 (17)0.0555 (12)0.0113 (12)0.0084 (11)0.0058 (11)
C10.0520 (19)0.059 (2)0.0570 (19)0.0083 (16)0.0193 (16)0.0046 (16)
C20.083 (3)0.065 (2)0.065 (2)0.003 (2)0.010 (2)0.0038 (19)
C30.090 (3)0.088 (3)0.075 (2)0.000 (3)0.011 (2)0.011 (2)
C40.083 (3)0.077 (3)0.119 (4)0.004 (2)0.026 (3)0.026 (3)
C50.102 (4)0.055 (3)0.140 (4)0.011 (2)0.000 (3)0.007 (3)
C60.087 (3)0.060 (2)0.095 (3)0.011 (2)0.005 (2)0.012 (2)
C70.0497 (19)0.056 (2)0.0580 (18)0.0007 (15)0.0127 (16)0.0038 (16)
C80.060 (2)0.075 (2)0.071 (2)0.0017 (18)0.0221 (18)0.0022 (18)
C90.063 (2)0.092 (3)0.083 (2)0.011 (2)0.031 (2)0.023 (2)
C100.062 (2)0.092 (3)0.092 (3)0.017 (2)0.020 (2)0.027 (2)
C110.084 (3)0.080 (3)0.093 (3)0.024 (2)0.020 (2)0.004 (2)
C120.070 (2)0.076 (3)0.075 (2)0.011 (2)0.0208 (19)0.004 (2)
N10.0588 (18)0.0722 (19)0.0668 (17)0.0040 (15)0.0214 (15)0.0004 (15)
N20.0641 (18)0.107 (2)0.0696 (19)0.0141 (17)0.0156 (16)0.0089 (17)
C130.061 (2)0.072 (2)0.059 (2)0.0053 (19)0.0153 (19)0.0150 (18)
C140.056 (2)0.099 (3)0.076 (2)0.005 (2)0.0184 (19)0.012 (2)
C150.065 (3)0.113 (3)0.094 (3)0.002 (2)0.037 (2)0.018 (3)
C160.083 (3)0.105 (3)0.087 (3)0.001 (2)0.046 (3)0.004 (2)
C170.084 (3)0.082 (3)0.075 (2)0.000 (2)0.027 (2)0.005 (2)
O30.0917 (17)0.0687 (15)0.0640 (14)0.0134 (14)0.0191 (13)0.0017 (12)
Geometric parameters (Å, º) top
P1—O21.498 (2)C10—C111.367 (5)
P1—O11.508 (2)C10—H80.9300
P1—C11.800 (3)C11—C121.379 (5)
P1—C71.801 (3)C11—H70.9300
C1—C61.376 (4)C12—H60.9300
C1—C21.383 (4)N1—C131.341 (4)
C2—C31.370 (5)N1—C171.355 (4)
C2—H50.9300N1—H1A0.8600
C3—C41.356 (5)N2—C131.329 (4)
C3—H40.9300N2—H130.8601
C4—C51.351 (5)N2—H140.8600
C4—H30.9300C13—C141.398 (4)
C5—C61.376 (5)C14—C151.353 (5)
C5—H20.9300C14—H180.9300
C6—H10.9300C15—C161.387 (5)
C7—C81.377 (4)C15—H170.9300
C7—C121.386 (4)C16—C171.337 (5)
C8—C91.379 (5)C16—H160.9300
C8—H100.9300C17—H150.9300
C9—C101.373 (5)O3—H3A0.954 (10)
C9—H90.9300O3—H3B0.953 (10)
O2—P1—O1116.01 (13)C8—C9—H9119.5
O2—P1—C1109.03 (14)C11—C10—C9118.7 (3)
O1—P1—C1107.64 (13)C11—C10—H8120.7
O2—P1—C7110.68 (13)C9—C10—H8120.7
O1—P1—C7108.71 (14)C10—C11—C12121.1 (4)
C1—P1—C7104.06 (14)C10—C11—H7119.5
C6—C1—C2117.0 (3)C12—C11—H7119.5
C6—C1—P1121.6 (3)C11—C12—C7120.4 (3)
C2—C1—P1121.3 (2)C11—C12—H6119.8
C3—C2—C1122.2 (3)C7—C12—H6119.8
C3—C2—H5118.9C13—N1—C17122.7 (3)
C1—C2—H5118.9C13—N1—H1A118.7
C4—C3—C2119.3 (4)C17—N1—H1A118.7
C4—C3—H4120.4C13—N2—H13120.3
C2—C3—H4120.4C13—N2—H14119.7
C5—C4—C3120.1 (4)H13—N2—H14120.0
C5—C4—H3119.9N2—C13—N1119.7 (3)
C3—C4—H3119.9N2—C13—C14122.9 (3)
C4—C5—C6120.9 (4)N1—C13—C14117.5 (3)
C4—C5—H2119.5C15—C14—C13120.0 (4)
C6—C5—H2119.5C15—C14—H18120.0
C1—C6—C5120.5 (4)C13—C14—H18120.0
C1—C6—H1119.8C14—C15—C16120.5 (4)
C5—C6—H1119.8C14—C15—H17119.7
C8—C7—C12118.3 (3)C16—C15—H17119.7
C8—C7—P1120.9 (2)C17—C16—C15118.9 (4)
C12—C7—P1120.8 (2)C17—C16—H16120.5
C7—C8—C9120.6 (3)C15—C16—H16120.5
C7—C8—H10119.7C16—C17—N1120.4 (4)
C9—C8—H10119.7C16—C17—H15119.8
C10—C9—C8120.9 (4)N1—C17—H15119.8
C10—C9—H9119.5H3A—O3—H3B104 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.861.802.655 (4)175
O3—H3A···O2i0.95 (2)1.79 (2)2.743 (3)175 (3)
O3—H3B···O10.95 (2)1.80 (2)2.744 (3)171 (3)
N2—H13···O20.862.022.881 (4)176
N2—H14···O3ii0.862.042.853 (4)157
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC5H7N2+·C12H10O2P·H2O
Mr330.31
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)15.2716 (19), 9.979 (2), 11.7671 (15)
β (°) 103.073 (10)
V3)1746.8 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.17
Crystal size (mm)0.60 × 0.35 × 0.21
Data collection
DiffractometerStoe IPDS-II
diffractometer
Absorption correctionAnalytical
(X-SHAPE; Stoe & Cie, 2007)
Tmin, Tmax0.813, 0.965
No. of measured, independent and
observed [I > 2σ(I)] reflections
8165, 2972, 1660
Rint0.097
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.130, 1.02
No. of reflections2972
No. of parameters214
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.21, 0.20

Computer programs: X-RED (Stoe & Cie, 2007), X-AREA (Stoe & Cie, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2001), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.861.802.655 (4)175
O3—H3A···O2i0.95 (2)1.79 (2)2.743 (3)175 (3)
O3—H3B···O10.95 (2)1.80 (2)2.744 (3)171 (3)
N2—H13···O20.862.022.881 (4)176
N2—H14···O3ii0.862.042.853 (4)157
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x, y+1/2, z+1/2.
 

Acknowledgements

This work was supported by a grant from the University of Tehran.

References

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