inorganic compounds
Disilver(I) trinickel(II) hydrogenphosphate bis(phosphate), Ag2Ni3(HPO4)(PO4)2
aLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: abder_assani@yahoo.fr
The title compound, Ag2Ni3(HPO4)(PO4)2, has been synthesized by the hydrothermal method. Its structure is formed by two types of chains running along the b axis. The first chain results from a linear and continuous succession of NiO6 octahedra linked to PO4 tetrahedra by a common vertex. The second chain is built up from two adjacent edge-sharing octahedra (dimers) whose ends are linked to two PO4 tetrahedra by a common edge. Those two types of chains are linked together by the phosphate groups to form polyhedral sheets parallel to the (001) plane. The three-dimensional framework delimits two types of hexagonal tunnels parallel to the a-axis direction, at (x, 1/2, 0) and (x, 0, 1/2), where the Ag atoms are located. Each silver cation is surrounded by eight O atoms. The same Ag+ coordination is found in other phosphates with the alluaudite structure, for example, AgMn3(PO4)(HPO4)2. Moreover, O—H⋯O hydrogen bonds link three PO4 tetrahedra so as to build a three-dimensional network.
Related literature
For related applications, see: Viter & Nagornyi (2009); Gao & Gao (2005); Clearfield (1988); Trad et al. (2010). For compounds with the same structure, see: Assani et al. (2010, 2011); Leroux et al. (1995); Ben Smail & Jouini (2002).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2005); cell SAINT; data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536811021167/ru2005sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811021167/ru2005Isup2.hkl
By means of hydrothermal synthesis, we have isolate a new silver nickel phosphate from the reaction mixture of silver nitrate (AgNO3; 0.1699 g), metallic nickel (Ni; 0.0881 g), 85%wt phosphoric acid (H3PO4; 0,10 ml) and water (12 ml). The hydrothermal treatment was conducted in a 23 ml Teflon-lined autoclave under autogeneous pressure at 468 K for two days. After being filtered off, washed with deionized water and air dried, the reaction product consists of a monophasic green powder and some green parallelepipedic crystals corresponding to the title compound.
The structure is solved by direct method technique and refined by full-matrix least-squares using SHELXS97 and SHELXL97 program packages. The structure
in the centrosymmetric was unsuccessful. Infact the crystal is a racemic twinned with a refined ratio of 0.479 (26), which explains the ambiguity in the The is not centro symmetric and the polar axis restraint is generated automatically by SHELXL program. Friedel opposites reflections are not merged. The O-bound H atom is initially located unambiguously in a difference map and refined with O—H distance restraints of 0.86 (1). In a the last cycle ther is refined in the riding model approximation with Uiso(H) set to 1.2Ueq(O). The highest and deepest hole residual peak in the final difference Fourier map are located at 0.72 Å and 0.62 Å, from Ag1.Data collection: APEX2 (Bruker, 2005); cell
APEX2 (Bruker, 2005); data reduction: APEX2 (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).Ag2Ni3(HPO4)(PO4)2 | F(000) = 1280 |
Mr = 677.79 | Dx = 4.974 Mg m−3 |
Orthorhombic, Ima2 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: I 2 -2a | Cell parameters from 1125 reflections |
a = 12.9233 (3) Å | θ = 3.2–29.0° |
b = 6.5678 (2) Å | µ = 10.98 mm−1 |
c = 10.6629 (3) Å | T = 296 K |
V = 905.04 (4) Å3 | Prism, green |
Z = 4 | 0.25 × 0.13 × 0.08 mm |
Bruker X8 APEXII CCD area-detector diffractometer | 1125 independent reflections |
Radiation source: fine-focus sealed tube | 1103 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.017 |
ϕ and ω scans | θmax = 29.0°, θmin = 3.2° |
Absorption correction: multi-scan (MULABS; Blessing, 1995) | h = −13→14 |
Tmin = 0.382, Tmax = 0.471 | k = −16→17 |
3762 measured reflections | l = −8→8 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.024 | H-atom parameters constrained |
wR(F2) = 0.060 | w = 1/[σ2(Fo2) + (0.0356P)2 + 1.7344P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max < 0.001 |
1125 reflections | Δρmax = 1.81 e Å−3 |
99 parameters | Δρmin = −1.12 e Å−3 |
1 restraint | Absolute structure: Flack (1983), 467 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.55 (3) |
Ag2Ni3(HPO4)(PO4)2 | V = 905.04 (4) Å3 |
Mr = 677.79 | Z = 4 |
Orthorhombic, Ima2 | Mo Kα radiation |
a = 12.9233 (3) Å | µ = 10.98 mm−1 |
b = 6.5678 (2) Å | T = 296 K |
c = 10.6629 (3) Å | 0.25 × 0.13 × 0.08 mm |
Bruker X8 APEXII CCD area-detector diffractometer | 1125 independent reflections |
Absorption correction: multi-scan (MULABS; Blessing, 1995) | 1103 reflections with I > 2σ(I) |
Tmin = 0.382, Tmax = 0.471 | Rint = 0.017 |
3762 measured reflections |
R[F2 > 2σ(F2)] = 0.024 | H-atom parameters constrained |
wR(F2) = 0.060 | Δρmax = 1.81 e Å−3 |
S = 1.06 | Δρmin = −1.12 e Å−3 |
1125 reflections | Absolute structure: Flack (1983), 467 Friedel pairs |
99 parameters | Absolute structure parameter: 0.55 (3) |
1 restraint |
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 | ||
Ag1 | 0.2500 | 0.60793 (8) | −0.01513 (7) | 0.02914 (18) | |
Ag2 | 0.0000 | 0.5000 | −0.03769 (5) | 0.0443 (2) | |
Ni1 | 0.13623 (4) | 0.24801 (10) | 0.20871 (7) | 0.00699 (13) | |
Ni2 | 0.0000 | 0.5000 | 0.45735 (7) | 0.00462 (15) | |
P1 | −0.07279 (7) | 0.25722 (19) | 0.20677 (13) | 0.00587 (19) | |
P2 | 0.2500 | 0.4102 (2) | 0.45653 (15) | 0.0042 (3) | |
O1 | −0.1343 (3) | 0.4456 (5) | 0.1739 (3) | 0.0091 (7) | |
O2 | 0.0044 (3) | 0.2070 (6) | 0.1000 (3) | 0.0056 (6) | |
O3 | 0.0036 (3) | 0.2785 (5) | 0.3204 (3) | 0.0072 (8) | |
O4 | −0.1494 (3) | 0.0786 (5) | 0.2360 (3) | 0.0096 (9) | |
O5 | 0.1543 (2) | 0.5443 (4) | 0.4552 (3) | 0.0085 (5) | |
O6 | 0.2500 | 0.2617 (8) | 0.3420 (5) | 0.0090 (12) | |
O7 | 0.2500 | 0.2692 (7) | 0.5756 (5) | 0.0064 (12) | |
H7 | 0.2500 | 0.3065 | 0.6529 | 0.008* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ag1 | 0.0491 (4) | 0.0158 (3) | 0.0225 (3) | 0.000 | 0.000 | 0.0048 (3) |
Ag2 | 0.1145 (7) | 0.0083 (2) | 0.0101 (3) | −0.0020 (3) | 0.000 | 0.000 |
Ni1 | 0.0058 (2) | 0.0092 (3) | 0.0060 (3) | 0.0005 (2) | 0.0005 (3) | −0.00135 (19) |
Ni2 | 0.0052 (3) | 0.0049 (3) | 0.0037 (3) | 0.0006 (2) | 0.000 | 0.000 |
P1 | 0.0064 (4) | 0.0064 (5) | 0.0047 (4) | −0.0001 (5) | 0.0008 (6) | 0.0004 (4) |
P2 | 0.0043 (6) | 0.0054 (6) | 0.0030 (7) | 0.000 | 0.000 | −0.0012 (6) |
O1 | 0.0086 (16) | 0.0100 (18) | 0.0088 (15) | 0.0003 (14) | −0.0017 (10) | −0.0010 (12) |
O2 | 0.0044 (18) | 0.0088 (15) | 0.0035 (15) | −0.0002 (15) | −0.0010 (12) | −0.0029 (13) |
O3 | 0.012 (2) | 0.0044 (17) | 0.0049 (15) | 0.0009 (15) | −0.0005 (12) | −0.0010 (12) |
O4 | 0.010 (2) | 0.0023 (18) | 0.016 (2) | −0.0011 (13) | 0.0015 (11) | 0.0017 (11) |
O5 | 0.0077 (12) | 0.0082 (12) | 0.0096 (15) | 0.0014 (10) | −0.0008 (13) | −0.0003 (12) |
O6 | 0.005 (3) | 0.013 (3) | 0.009 (2) | 0.000 | 0.000 | −0.0007 (16) |
O7 | 0.007 (3) | 0.007 (3) | 0.005 (2) | 0.000 | 0.000 | 0.0023 (16) |
Ag1—O1i | 2.534 (3) | Ni2—O2xi | 2.041 (3) |
Ag1—O1ii | 2.535 (3) | Ni2—O3i | 2.062 (4) |
Ag1—O5iii | 2.617 (3) | Ni2—O3 | 2.062 (4) |
Ag1—O5iv | 2.617 (3) | P1—O1 | 1.511 (4) |
Ag1—O7v | 2.659 (5) | P1—O2 | 1.549 (4) |
Ag1—O6v | 2.866 (5) | P1—O4 | 1.566 (4) |
Ag1—O4vi | 2.962 (3) | P1—O3 | 1.569 (4) |
Ag1—O4vii | 2.962 (3) | P2—O5 | 1.518 (3) |
Ag1—Ag2 | 3.3164 (2) | P2—O5xii | 1.518 (3) |
Ag2—O3vi | 2.375 (4) | P2—O6 | 1.563 (6) |
Ag2—O3viii | 2.375 (4) | P2—O7 | 1.572 (5) |
Ag2—O2 | 2.421 (4) | O1—Ni1i | 2.046 (4) |
Ag2—O2i | 2.421 (4) | O1—O4 | 2.507 (5) |
Ag2—O1 | 2.869 (4) | O1—Ag1i | 2.534 (3) |
Ag2—O1i | 2.869 (4) | O2—Ni2xiii | 2.041 (3) |
Ag2—O4viii | 3.133 (4) | O3—Ag2xiv | 2.375 (4) |
Ag2—O4vi | 3.133 (4) | O4—Ni1ix | 2.172 (4) |
Ni1—O1i | 2.046 (4) | O4—Ag1xv | 2.962 (3) |
Ni1—O7v | 2.047 (3) | O4—Ag2xiv | 3.133 (4) |
Ni1—O6 | 2.047 (4) | O5—Ag1xvi | 2.617 (3) |
Ni1—O2 | 2.079 (4) | O6—Ni1xii | 2.047 (4) |
Ni1—O3 | 2.097 (4) | O6—Ag1xvii | 2.866 (5) |
Ni1—O4ix | 2.172 (4) | O7—Ni1xi | 2.047 (3) |
Ni2—O5i | 2.015 (3) | O7—Ni1xvii | 2.047 (3) |
Ni2—O5 | 2.015 (3) | O7—Ag1xvii | 2.659 (5) |
Ni2—O2x | 2.041 (3) | O7—H7 | 0.8600 |
O1i—Ag1—O1ii | 72.33 (16) | O3viii—Ag2—O4vi | 67.92 (11) |
O1i—Ag1—O5iii | 86.46 (10) | O2—Ag2—O4vi | 125.71 (11) |
O1ii—Ag1—O5iii | 119.74 (11) | O2i—Ag2—O4vi | 110.51 (11) |
O1i—Ag1—O5iv | 119.74 (11) | O1—Ag2—O4vi | 177.43 (10) |
O1ii—Ag1—O5iv | 86.46 (10) | O1i—Ag2—O4vi | 102.27 (8) |
O5iii—Ag1—O5iv | 56.41 (12) | O4viii—Ag2—O4vi | 79.25 (12) |
O1i—Ag1—O7v | 65.26 (11) | Ag1i—Ag2—Ag1 | 171.68 (3) |
O1ii—Ag1—O7v | 65.26 (11) | O1i—Ni1—O7v | 86.42 (17) |
O5iii—Ag1—O7v | 148.99 (7) | O1i—Ni1—O6 | 95.26 (18) |
O5iv—Ag1—O7v | 148.99 (7) | O7v—Ni1—O6 | 88.15 (12) |
O1i—Ag1—O6v | 107.78 (12) | O1i—Ni1—O2 | 90.92 (15) |
O1ii—Ag1—O6v | 107.78 (12) | O7v—Ni1—O2 | 101.25 (13) |
O5iii—Ag1—O6v | 132.46 (11) | O6—Ni1—O2 | 169.08 (15) |
O5iv—Ag1—O6v | 132.46 (11) | O1i—Ni1—O3 | 89.93 (14) |
O7v—Ag1—O6v | 53.46 (12) | O7v—Ni1—O3 | 170.53 (14) |
O1i—Ag1—O4vi | 116.39 (11) | O6—Ni1—O3 | 100.89 (14) |
O1ii—Ag1—O4vi | 164.32 (10) | O2—Ni1—O3 | 70.05 (11) |
O5iii—Ag1—O4vi | 74.98 (10) | O1i—Ni1—O4ix | 175.34 (13) |
O5iv—Ag1—O4vi | 98.97 (10) | O7v—Ni1—O4ix | 88.97 (17) |
O7v—Ag1—O4vi | 105.40 (12) | O6—Ni1—O4ix | 83.92 (17) |
O6v—Ag1—O4vi | 57.90 (11) | O2—Ni1—O4ix | 90.62 (14) |
O1i—Ag1—O4vii | 164.32 (10) | O3—Ni1—O4ix | 94.73 (14) |
O1ii—Ag1—O4vii | 116.39 (11) | O5i—Ni2—O5 | 178.70 (19) |
O5iii—Ag1—O4vii | 98.97 (10) | O5i—Ni2—O2x | 94.43 (14) |
O5iv—Ag1—O4vii | 74.98 (10) | O5—Ni2—O2x | 86.54 (14) |
O7v—Ag1—O4vii | 105.40 (12) | O5i—Ni2—O2xi | 86.55 (14) |
O6v—Ag1—O4vii | 57.90 (11) | O5—Ni2—O2xi | 94.42 (14) |
O4vi—Ag1—O4vii | 52.10 (14) | O2x—Ni2—O2xi | 83.6 (2) |
O3vi—Ag2—O3viii | 100.81 (18) | O5i—Ni2—O3i | 94.10 (14) |
O3vi—Ag2—O2 | 177.72 (14) | O5—Ni2—O3i | 84.97 (15) |
O3viii—Ag2—O2 | 76.92 (10) | O2x—Ni2—O3i | 93.29 (11) |
O3vi—Ag2—O2i | 76.92 (10) | O2xi—Ni2—O3i | 176.91 (18) |
O3viii—Ag2—O2i | 177.72 (14) | O5i—Ni2—O3 | 84.97 (15) |
O2—Ag2—O2i | 105.35 (15) | O5—Ni2—O3 | 94.10 (14) |
O3vi—Ag2—O1 | 125.84 (12) | O2x—Ni2—O3 | 176.91 (18) |
O3viii—Ag2—O1 | 114.65 (11) | O2xi—Ni2—O3 | 93.29 (11) |
O2—Ag2—O1 | 55.82 (11) | O3i—Ni2—O3 | 89.8 (2) |
O2i—Ag2—O1 | 66.92 (11) | O1—P1—O2 | 110.0 (2) |
O3vi—Ag2—O1i | 114.65 (11) | O1—P1—O4 | 109.1 (2) |
O3viii—Ag2—O1i | 125.84 (12) | O2—P1—O4 | 113.2 (2) |
O2—Ag2—O1i | 66.92 (11) | O1—P1—O3 | 115.89 (19) |
O2i—Ag2—O1i | 55.82 (11) | O2—P1—O3 | 100.46 (15) |
O1—Ag2—O1i | 76.28 (13) | O4—P1—O3 | 108.1 (2) |
O3vi—Ag2—O4viii | 67.92 (11) | O5—P2—O5xii | 109.1 (2) |
O3viii—Ag2—O4viii | 52.70 (12) | O5—P2—O6 | 110.77 (16) |
O2—Ag2—O4viii | 110.51 (11) | O5xii—P2—O6 | 110.77 (16) |
O2i—Ag2—O4viii | 125.71 (11) | O5—P2—O7 | 110.44 (16) |
O1—Ag2—O4viii | 102.27 (8) | O5xii—P2—O7 | 110.44 (16) |
O1i—Ag2—O4viii | 177.43 (10) | O6—P2—O7 | 105.3 (2) |
O3vi—Ag2—O4vi | 52.70 (12) | P2—O7—H7 | 127.4 |
Symmetry codes: (i) −x, −y+1, z; (ii) x+1/2, −y+1, z; (iii) x, −y+3/2, z−1/2; (iv) −x+1/2, −y+3/2, z−1/2; (v) −x+1/2, −y+1/2, z−1/2; (vi) −x, y+1/2, z−1/2; (vii) x+1/2, y+1/2, z−1/2; (viii) x, −y+1/2, z−1/2; (ix) −x, −y, z; (x) −x, y+1/2, z+1/2; (xi) x, −y+1/2, z+1/2; (xii) −x+1/2, y, z; (xiii) −x, y−1/2, z−1/2; (xiv) −x, y−1/2, z+1/2; (xv) x−1/2, y−1/2, z+1/2; (xvi) −x+1/2, −y+3/2, z+1/2; (xvii) −x+1/2, −y+1/2, z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O7—H7···O6xvii | 0.86 | 2.06 | 2.847 (6) | 151 |
Symmetry code: (xvii) −x+1/2, −y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | Ag2Ni3(HPO4)(PO4)2 |
Mr | 677.79 |
Crystal system, space group | Orthorhombic, Ima2 |
Temperature (K) | 296 |
a, b, c (Å) | 12.9233 (3), 6.5678 (2), 10.6629 (3) |
V (Å3) | 905.04 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 10.98 |
Crystal size (mm) | 0.25 × 0.13 × 0.08 |
Data collection | |
Diffractometer | Bruker X8 APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (MULABS; Blessing, 1995) |
Tmin, Tmax | 0.382, 0.471 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3762, 1125, 1103 |
Rint | 0.017 |
(sin θ/λ)max (Å−1) | 0.682 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.024, 0.060, 1.06 |
No. of reflections | 1125 |
No. of parameters | 99 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.81, −1.12 |
Absolute structure | Flack (1983), 467 Friedel pairs |
Absolute structure parameter | 0.55 (3) |
Computer programs: APEX2 (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O7—H7···O6i | 0.86 | 2.06 | 2.847 (6) | 151.0 |
Symmetry code: (i) −x+1/2, −y+1/2, z+1/2. |
Acknowledgements
The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.
References
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As the improvement has arisen in the synthesis of a variety of interesting porous materials and open-framework structures, extensive studies are devoted to the metal phosphates which exhibit a rich structural diversity and have been widely studied as catalysts (Viter & Nagornyi, 2009; Gao & Gao, 2005), ion-exchangers (Clearfield, 1988) and as positive electrode in the lithium and sodium batteries (Trad et al. (2010)).
Within this family of compounds, the resulting anionic frameworks, generally constructed from the alternation of PO4 tetrahedra connected to metal cations in different coordinate geometry MOn (with n=4, 5 and 6), generate pores and channels offering suitable environment to accommodate different other cations. In our search for new phosphates with microporous framework, our most attention has been paid to the hydrothermal investigation of the A2O—MO—P2O5 systems, with A = monovalent cations and M = divalent cations. Accordingly, we have succeed, for instance, to isolate new form of silver zinc phosphate (γ-AgZnPO4) related to the ABW zeolite structure (Assani et al. 2010) while the silver magnesium phosphate, namely AgMg3(PO4)(HPO4)2, represent a new member of the well known alluaudite-like structure family (Assani et al. 2011). The present paper aims to develop the hydrothermal synthesis and the structural characterization of a new silver nickel phosphate, namely, Ag2Ni3(HPO4)(PO4)2.
The structure of this compound is formed by two types of chains running along the b axis. The first chain (Ni2P2HO9)∞ is built up from Ni2 and P2 atoms in special Wyckoff position 4 b (m) of the space group Ima2. This chain results from linear and continuous succession of octahedron (Ni2O6) and P2O3OH tetrahedron which share a vertex. The second chain (Ni2P2O14)n is built up from two adjacent edge sharing octahedra ((Ni1)2O10 dimmers) whose ends are linked to two P1O4 tetrahedra by a common edge (Fig.1). Those chains are linked together by the phosphate groups to form polyhedral sheets parallel to the (0 0 1) plane as shown in Fig.2.
The three dimensional framework delimits two types of hexagonal tunnels running along the a direction, at x 1/2 0 and x 0 1/2 (Fig.3). The Ag2 atom is located at centre of tunnels, this explains the high value of its anisotropic displacement U11, whereas Ag1 is slightly shifted from this center (Wyckoff positions: Ag2 at 2a: 0, 0, z and Ag1 at 2 b: 1/4, y, z). However, each Ag+ ion is surrounded by 8 O atoms with different Ag–O distances. Indeed, the first coordination environment of Ag2+ is almost square planar with four short Ag2—O distances between 2.373 (4) and 2.421 (4) Å and the other four larger distances are in the range of 2.869 (4) to 3.133 (4) Å. A similar coordination surrounding Ag1+ is observed with Ag1—O bond lengths in the range of 2.537 (4)–2.616 (4) Å and the longest bonds are situated between 2.661 (4) and 2.963 (4) Å. The same coordination for this cation is found in other phosphate with alluaudite structure like AgMn3(PO4)(HPO4)2 (Leroux et al. (1995)) and AgNi3(PO4)(HPO4)2 (Ben Smail & Jouini (2002)).
Moreover, O—H···O hydrogen bondings link two adjacent P2O4 tetrahedra via a strong hydrogen bond O7–H7···O6 to two P1O4 tetrahedra through weak bonds O7–H7···O4 in the way to build an infinite three-dimensional network as shown in Table 1.