inorganic compounds
Dilead(II) hydrogenphosphite dinitrate
aLaboratoire d'Ingénierie des Matériaux Organométalliques et Moléculaires, `LIMOM', Département de Chimie, Faculté des Sciences, BP 1796, Fès-Atlas, 30000 Fès, Morocco, bInstitute of Physics, Na Slovance 2, 182 21 Praha 8, Czech Republic, and cLaboratory of Mineral, Solid and Analytical Chemistry, `LCSMA', Department of Chemistry, Faculty of Sciences, University Mohamed I, PO Box 717, 60000 Oujda, Morocco
*Correspondence e-mail: belbali@fso.ump.ma
In the title compound, Pb2(HPO3)(NO3)2, the two distinct Pb2+ ions (both with m) adopt irregular PbO10 coordination polyhedra. The structure is completed by two distinct nitrate groups (in which one O atom and the N atom have m for both ions) and an HPO32− anion (in which one O atom and the P and H atoms have m site symmetry). The connectivity of the PbO10, NO3 and HPO3 units in the results in a three-dimensional network.
Related literature
For related structures, see: Ouarsal et al. (2005a,b); Vasić et al. (1981). For bond-valence sum calculations, see: Brown & Altermatt (1985).
Experimental
Crystal data
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Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED; program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: JANA2006 (Petříček et al., 2006); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2006.
Supporting information
10.1107/S1600536809014469/hb2952sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809014469/hb2952Isup2.hkl
1.6161 g lead nitrate Pb(NO3)2.6H2O was dissolved in 6 ml of distilled water and added to a solution of 0.4 g phosphorous acid H3PO3, dissolved in 5 ml water. The mixture was stirred for 1 h at 333 K, after which time the precipitate obtained was filtered out of the solution. The filtrate was allowed to stand at room temperature until many large, colourless needles of (I) arose. The crystals were recovered by filtration and washed with a water–ethanol (80:20 v/v) mixture.
The H atom was located in a difference map and its position and Uiso values were freely refined.
Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell
CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: JANA2006 (Petříček et al., 2006); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2006 (Petříček et al., 2006).Fig. 1. A view of the asymmetric unit and some symmetry-related atoms of (I) showing 60% probability displacement ellipsoids. The various bonds lengths are distinguished by colours and style: indigo-thick up to 2.514 Å, yellow-thick from 2.707 Å to 3.042 Å, yellow-thin-dashed for 3.168 Å. [Symmetry codes: (i) x, y, -1 + z; (ii) 1/2 - x, 1 - y, -1/2 + z; (iii) 3/2 - x, 1 - y, -1/2 + z; (iv) -1/2 - x, 1 - y, -1/2 + z; (v) 1 - x, y, -1 + z; (vi) 1 + x, 1 + y, -1 + z; (vii) -x, 1 + y, -1 + z; (viii) x, 1 + y, -1 + z; (ix) 1/2 + x, 1 - y, -3/2 + z; (x) 1/2 - x, 1 - y, -3/2 + z] | |
Fig. 2. A view of the structure of the title compound along [010]. The HPO3 groups are indicated as pink tetraedra. The bonds to Pb are omitted for clarity. The black thick rectangles denote the layers that will be plotted in more details in Fig. 3. | |
Fig. 3. The layers indicated in Fig. 2 in a view along the a direction. The first layer (grey, blue and red atoms) is plotted together with all coordinated O atoms. The various bonds lengths are distinguished by the same way as in Fig. 1. |
Pb2(HPO3)(NO3)2 | F(000) = 532 |
Mr = 618.4 | Dx = 5.070 Mg m−3 |
Orthorhombic, Pmn21 | Mo Kα radiation, λ = 0.71069 Å |
Hall symbol: P 2ac -2 | Cell parameters from 6814 reflections |
a = 5.4069 (2) Å | θ = 3.4–26.5° |
b = 10.4079 (6) Å | µ = 41.76 mm−1 |
c = 7.1958 (4) Å | T = 120 K |
V = 404.94 (4) Å3 | Plate, colourless |
Z = 2 | 0.25 × 0.10 × 0.05 mm |
Oxford Diffraction CCD diffractometer | 932 independent reflections |
Radiation source: X-ray tube | 919 reflections with I > 3σ(I) |
Graphite monochromator | Rint = 0.026 |
Detector resolution: 8.3438 pixels mm-1 | θmax = 26.5°, θmin = 3.4° |
Rotation method data acquisition using ω scans | h = −6→6 |
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008) | k = −13→13 |
Tmin = 0.013, Tmax = 0.156 | l = −9→9 |
6814 measured reflections |
Refinement on F2 | Weighting scheme based on measured s.u.'s w = 1/[σ2(I) + 0.0004I2] |
R[F2 > 2σ(F2)] = 0.012 | (Δ/σ)max = 0.013 |
wR(F2) = 0.030 | Δρmax = 0.94 e Å−3 |
S = 1.25 | Δρmin = −0.53 e Å−3 |
932 reflections | Extinction correction: B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974) |
78 parameters | Extinction coefficient: 48 (5) |
1 restraint | Absolute structure: Flack (1983), with 431 Friedel pairs |
1 constraint | Absolute structure parameter: 0.01 (1) |
Only H-atom coordinates refined |
Pb2(HPO3)(NO3)2 | V = 404.94 (4) Å3 |
Mr = 618.4 | Z = 2 |
Orthorhombic, Pmn21 | Mo Kα radiation |
a = 5.4069 (2) Å | µ = 41.76 mm−1 |
b = 10.4079 (6) Å | T = 120 K |
c = 7.1958 (4) Å | 0.25 × 0.10 × 0.05 mm |
Oxford Diffraction CCD diffractometer | 932 independent reflections |
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008) | 919 reflections with I > 3σ(I) |
Tmin = 0.013, Tmax = 0.156 | Rint = 0.026 |
6814 measured reflections |
R[F2 > 2σ(F2)] = 0.012 | Only H-atom coordinates refined |
wR(F2) = 0.030 | Δρmax = 0.94 e Å−3 |
S = 1.25 | Δρmin = −0.53 e Å−3 |
932 reflections | Absolute structure: Flack (1983), with 431 Friedel pairs |
78 parameters | Absolute structure parameter: 0.01 (1) |
1 restraint |
Refinement. The refinement was carried out against all reflections. The conventional R-factor is always based on F. The goodness of fit as well as the weighted R-factor are based on F and F2 for refinement carried out on F and F2, respectively. The threshold expression is used only for calculating R-factors etc. and it is not relevant to the choice of reflections for refinement. The program used for refinement, JANA2000, uses the weighting scheme based on the experimental expectations, see _refine_ls_weighting_details, that does not force S to be one. Therefore the values of S are usually larger then the ones from the SHELX program. |
x | y | z | Uiso*/Ueq | ||
Pb1 | 0.5 | 0.47428 (2) | 0.20948 | 0.01003 (7) | |
Pb2 | 0.5 | 0.84356 (2) | 0.37011 (5) | 0.01002 (8) | |
O1 | 0.5 | 0.4667 (5) | 0.5354 (8) | 0.0147 (15) | |
P1 | 0.5 | 0.34607 (15) | 0.6573 (3) | 0.0083 (5) | |
N1 | 0 | −0.0035 (6) | 0.4972 (8) | 0.0103 (17) | |
O2 | 0 | −0.0975 (5) | 0.3893 (8) | 0.0155 (14) | |
N2 | 0.5 | 0.7144 (6) | 0.7547 (8) | 0.0134 (18) | |
O3 | 0.2358 (7) | 0.6561 (4) | 0.2748 (5) | 0.0109 (10) | |
O4 | 0.7011 (7) | 0.7548 (3) | 0.6898 (6) | 0.0205 (11) | |
O5 | −0.2007 (7) | 0.0434 (3) | 0.5539 (6) | 0.0194 (11) | |
O6 | 0.5 | 0.6317 (6) | 0.8801 (10) | 0.033 (2) | |
H1 | 0.5 | 0.248 (4) | 0.568 (10) | 0.0099* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Pb1 | 0.00890 (14) | 0.01098 (13) | 0.01022 (12) | 0 | 0 | −0.00077 (12) |
Pb2 | 0.00891 (15) | 0.01137 (12) | 0.00978 (12) | 0 | 0 | −0.00032 (9) |
O1 | 0.012 (3) | 0.020 (2) | 0.013 (2) | 0 | 0 | 0.002 (2) |
P1 | 0.0048 (9) | 0.0110 (8) | 0.0091 (9) | 0 | 0 | 0.0017 (5) |
N1 | 0.011 (3) | 0.013 (2) | 0.007 (3) | 0 | 0 | 0.000 (2) |
O2 | 0.012 (3) | 0.015 (2) | 0.019 (2) | 0 | 0 | −0.006 (2) |
N2 | 0.019 (4) | 0.011 (3) | 0.010 (3) | 0 | 0 | 0.000 (2) |
O3 | 0.0055 (18) | 0.0151 (16) | 0.0123 (17) | −0.0002 (15) | 0.0003 (14) | −0.0033 (11) |
O4 | 0.0123 (19) | 0.0226 (16) | 0.027 (2) | −0.0012 (15) | −0.0004 (16) | 0.0012 (17) |
O5 | 0.013 (2) | 0.0235 (17) | 0.0222 (16) | 0.0054 (16) | 0.0001 (18) | −0.0102 (17) |
O6 | 0.049 (4) | 0.030 (3) | 0.019 (3) | 0 | 0 | 0.015 (3) |
Pb1—O1 | 2.346 (6) | Pb2—O4iii | 2.707 (4) |
Pb1—O1i | 3.042 (3) | Pb2—O5vii | 2.948 (4) |
Pb1—O1ii | 3.042 (3) | Pb2—O5i | 2.782 (4) |
Pb1—O3 | 2.418 (4) | Pb2—O5viii | 2.782 (4) |
Pb1—O3iii | 2.418 (4) | Pb2—O5ix | 2.948 (4) |
Pb1—O4ii | 2.884 (4) | P1—O1 | 1.532 (6) |
Pb1—O4iv | 2.884 (4) | P1—O3x | 1.530 (4) |
Pb1—O6v | 2.881 (7) | P1—O3xi | 1.530 (4) |
Pb1—O6i | 3.168 (4) | P1—H1 | 1.20 (5) |
Pb1—O6ii | 3.168 (4) | N1—O2 | 1.249 (8) |
Pb2—O2vi | 2.7756 (11) | N1—O5 | 1.258 (5) |
Pb2—O2vii | 2.7756 (11) | N1—O5xii | 1.258 (5) |
Pb2—O3 | 2.513 (4) | N2—O4 | 1.255 (5) |
Pb2—O3iii | 2.513 (4) | N2—O4iii | 1.255 (5) |
Pb2—O4 | 2.707 (4) | N2—O6 | 1.247 (9) |
O1—Pb1—O1i | 114.73 (10) | O2vii—Pb2—O5i | 64.37 (14) |
O1—Pb1—O1ii | 114.73 (10) | O2vii—Pb2—O5viii | 109.11 (14) |
O1—Pb1—O3 | 80.31 (13) | O2vii—Pb2—O5ix | 110.88 (13) |
O1—Pb1—O3iii | 80.31 (13) | O3—Pb2—O3iii | 69.28 (12) |
O1—Pb1—O4ii | 91.22 (13) | O3—Pb2—O4 | 101.25 (12) |
O1—Pb1—O4iv | 91.22 (13) | O3—Pb2—O4iii | 74.85 (12) |
O1—Pb1—O6v | 147.26 (18) | O3—Pb2—O5vii | 169.07 (12) |
O1—Pb1—O6i | 66.48 (13) | O3—Pb2—O5i | 109.08 (12) |
O1—Pb1—O6ii | 66.48 (13) | O3—Pb2—O5viii | 83.30 (11) |
O1i—Pb1—O1ii | 125.41 (13) | O3—Pb2—O5ix | 110.97 (11) |
O1i—Pb1—O3 | 52.92 (13) | O3iii—Pb2—O4 | 74.85 (12) |
O1i—Pb1—O3iii | 116.57 (13) | O3iii—Pb2—O4iii | 101.25 (12) |
O1i—Pb1—O4ii | 130.14 (13) | O3iii—Pb2—O5vii | 110.97 (11) |
O1i—Pb1—O4iv | 69.42 (12) | O3iii—Pb2—O5i | 83.30 (11) |
O1i—Pb1—O6v | 63.03 (9) | O3iii—Pb2—O5viii | 109.08 (12) |
O1i—Pb1—O6i | 58.09 (14) | O3iii—Pb2—O5ix | 169.07 (12) |
O1i—Pb1—O6ii | 171.25 (15) | O4—Pb2—O4iii | 47.35 (12) |
O1ii—Pb1—O3 | 116.57 (13) | O4—Pb2—O5vii | 68.85 (11) |
O1ii—Pb1—O3iii | 52.92 (13) | O4—Pb2—O5i | 133.06 (12) |
O1ii—Pb1—O4ii | 69.42 (12) | O4—Pb2—O5viii | 174.94 (11) |
O1ii—Pb1—O4iv | 130.14 (13) | O4—Pb2—O5ix | 94.59 (12) |
O1ii—Pb1—O6v | 63.03 (9) | O4iii—Pb2—O5vii | 94.59 (12) |
O1ii—Pb1—O6i | 171.25 (15) | O4iii—Pb2—O5i | 174.94 (11) |
O1ii—Pb1—O6ii | 58.09 (14) | O4iii—Pb2—O5viii | 133.06 (12) |
O3—Pb1—O3iii | 72.44 (12) | O4iii—Pb2—O5ix | 68.85 (11) |
O3—Pb1—O4ii | 171.11 (12) | O5vii—Pb2—O5i | 81.63 (12) |
O3—Pb1—O4iv | 109.00 (12) | O5vii—Pb2—O5viii | 106.42 (11) |
O3—Pb1—O6v | 73.43 (14) | O5vii—Pb2—O5ix | 66.57 (11) |
O3—Pb1—O6i | 72.12 (14) | O5i—Pb2—O5viii | 45.92 (11) |
O3—Pb1—O6ii | 134.56 (15) | O5i—Pb2—O5ix | 106.42 (11) |
O3iii—Pb1—O4ii | 109.00 (12) | O5viii—Pb2—O5ix | 81.63 (12) |
O3iii—Pb1—O4iv | 171.11 (12) | Pb1—O1—P1 | 126.8 (3) |
O3iii—Pb1—O6v | 73.43 (14) | O1—P1—O3x | 109.20 (18) |
O3iii—Pb1—O6i | 134.56 (15) | O1—P1—O3xi | 109.20 (18) |
O3iii—Pb1—O6ii | 72.12 (14) | O1—P1—H1 | 113 (3) |
O4ii—Pb1—O4iv | 68.18 (11) | O3x—P1—O3xi | 112.8 (2) |
O4ii—Pb1—O6v | 115.45 (13) | O3x—P1—H1 | 106.4 (16) |
O4ii—Pb1—O6i | 102.09 (13) | O3xi—P1—H1 | 106.4 (16) |
O4ii—Pb1—O6ii | 41.64 (14) | O2—N1—O5 | 120.4 (3) |
O4iv—Pb1—O6v | 115.45 (13) | O2—N1—O5xii | 120.4 (3) |
O4iv—Pb1—O6i | 41.64 (14) | O5—N1—O5xii | 119.3 (5) |
O4iv—Pb1—O6ii | 102.09 (13) | Pb2xiii—O2—Pb2xiv | 153.8 (2) |
O6v—Pb1—O6i | 121.12 (11) | Pb2xiii—O2—N1 | 101.78 (11) |
O6v—Pb1—O6ii | 121.12 (11) | O4—N2—O4iii | 120.0 (5) |
O6i—Pb1—O6ii | 117.19 (15) | O4—N2—O6 | 120.0 (3) |
O2vi—Pb2—O2vii | 153.82 (14) | O4iii—N2—O6 | 120.0 (3) |
O2vi—Pb2—O3 | 68.37 (13) | Pb1—O3—Pb2 | 108.96 (14) |
O2vi—Pb2—O3iii | 137.63 (13) | Pb1—O3—P1i | 111.9 (2) |
O2vi—Pb2—O4 | 115.10 (14) | Pb2—O3—P1i | 129.5 (2) |
O2vi—Pb2—O4iii | 69.02 (14) | Pb1xv—O4—Pb2 | 123.29 (14) |
O2vi—Pb2—O5vii | 110.88 (13) | Pb1xv—O4—N2 | 101.0 (3) |
O2vi—Pb2—O5i | 109.11 (14) | Pb2—O4—N2 | 94.7 (3) |
O2vi—Pb2—O5viii | 64.37 (14) | Pb2xiii—O5—Pb2x | 151.56 (16) |
O2vi—Pb2—O5ix | 44.54 (13) | Pb2xiii—O5—N1 | 93.1 (3) |
O2vii—Pb2—O3 | 137.63 (13) | Pb2x—O5—N1 | 95.3 (3) |
O2vii—Pb2—O3iii | 68.37 (13) | Pb1xvi—O6—N2 | 171.0 (5) |
O2vii—Pb2—O4 | 69.02 (14) | Pb1xvi—O6—O4 | 148.84 (17) |
O2vii—Pb2—O4iii | 115.10 (14) | Pb1xvi—O6—O4iii | 148.84 (17) |
O2vii—Pb2—O5vii | 44.54 (13) |
Symmetry codes: (i) −x+1/2, −y+1, z−1/2; (ii) −x+3/2, −y+1, z−1/2; (iii) −x+1, y, z; (iv) x−1/2, −y+1, z−1/2; (v) x, y, z−1; (vi) x, y+1, z; (vii) x+1, y+1, z; (viii) x+1/2, −y+1, z−1/2; (ix) −x, y+1, z; (x) −x+1/2, −y+1, z+1/2; (xi) x+1/2, −y+1, z+1/2; (xii) −x, y, z; (xiii) x−1, y−1, z; (xiv) x, y−1, z; (xv) −x+3/2, −y+1, z+1/2; (xvi) x, y, z+1. |
Experimental details
Crystal data | |
Chemical formula | Pb2(HPO3)(NO3)2 |
Mr | 618.4 |
Crystal system, space group | Orthorhombic, Pmn21 |
Temperature (K) | 120 |
a, b, c (Å) | 5.4069 (2), 10.4079 (6), 7.1958 (4) |
V (Å3) | 404.94 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 41.76 |
Crystal size (mm) | 0.25 × 0.10 × 0.05 |
Data collection | |
Diffractometer | Oxford Diffraction CCD diffractometer |
Absorption correction | Analytical (CrysAlis RED; Oxford Diffraction, 2008) |
Tmin, Tmax | 0.013, 0.156 |
No. of measured, independent and observed [I > 3σ(I)] reflections | 6814, 932, 919 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.628 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.012, 0.030, 1.25 |
No. of reflections | 932 |
No. of parameters | 78 |
No. of restraints | 1 |
H-atom treatment | Only H-atom coordinates refined |
Δρmax, Δρmin (e Å−3) | 0.94, −0.53 |
Absolute structure | Flack (1983), with 431 Friedel pairs |
Absolute structure parameter | 0.01 (1) |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2008), SIR97 (Altomare et al., 1999), JANA2006 (Petříček et al., 2006), DIAMOND (Brandenburg & Putz, 2005).
Pb1—O1 | 2.346 (6) | Pb2—O2v | 2.7756 (11) |
Pb1—O1i | 3.042 (3) | Pb2—O3ii | 2.513 (4) |
Pb1—O3ii | 2.418 (4) | Pb2—O4ii | 2.707 (4) |
Pb1—O4iii | 2.884 (4) | Pb2—O5vi | 2.782 (4) |
Pb1—O6iv | 2.881 (7) | Pb2—O5vii | 2.948 (4) |
Pb1—O6i | 3.168 (4) |
Symmetry codes: (i) −x+3/2, −y+1, z−1/2; (ii) −x+1, y, z; (iii) x−1/2, −y+1, z−1/2; (iv) x, y, z−1; (v) x+1, y+1, z; (vi) x+1/2, −y+1, z−1/2; (vii) −x, y+1, z. |
Acknowledgements
This work was supported by the Grant Agency of the Czech Republic (grant No. 202/06/0757).
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
As part of our ongoing structural stuides of metal hydrogenphosphites (Ouarsal et al. 2005a,b) we now report on the preparation and crystal structure of the title compound, (I).
The structure of (I) consists of two symmetry-independent nitrate groups and one HPO3 hydrogenphosphite tetrahedron. The Pb atoms are located between them in two different crystallographic positions, both of them being irregularly coordinated by ten O atoms (Fig. 1). In the coordination of Pb1, shorter bonds occur causing larger bond valence sum (Brown & Altermatt, 1985) [2.028 (10) and 1.917 (6) for Pb(1)O10 and Pb(2)O10, respectively]. On the other hand, the mean Pb—O distance is rather larger in Pb(1)O10 than in Pb(2)O10, respectively 2.835 (5) Å and 2.745 (6) Å. These values are comparable to those reported in Pb(H2PO4)2, 2.617 Å (Vasić et al., 1981). One can distinguish the two decahedrons by their respective coordination forms: one monodentate NO3 and one monodentate HPO3 occurs in the coordination of Pb1, while two bidentate NO3 contribute to that of Pb2. Accordingly, the polyhedron Pb(1)O10 turns to be more distorted as Pb(2)O10.
Pb2(HPO3)(NO3)2 is characterized by a three-dimensional network. Although this is not a layer structure it is convenient from the explanatory point of view to distinguish two layers as indicated in Fig. 2. The slightly rotated view of a layer along [100] (Fig. 3) reveals strips extended in the c directions that are not interconnected within the same layer. Their connection in the b direction is mediated via the neighbouring layer which is shifted so that its Pb atoms fall into the holes. The shortest Pb—O bonds participate in the connection of the two PbO10 units and in the bond towards the HPO3 tetrahedron. As expected, H1 atom bonded to P is not involved in any hydrogen bonding. Average P—O distance and O—P—O and H—P—O angles are 1.531 (5) Å, 110.4 (2)° and 108.6 (2)° respectively. dP—H = 1.20 (5) Å. These values lie in the same range as the ones previously reported in known phosphites (Ouarsal et al. 2005b).