Silver indium diphosphate, AgInP₂O₇

Polycrystalline material of the title compound, AgInP₂O₇, was synthesized by traditional high-temperature solid-state methods and single crystals were grown from the melt of a mixture of AgInP₂O₇ and B₂O₃ as flux in a platinium crucible. The structure consists of InO₆ octa­hedra, which are corner-shared to PO₄ tetra­hedra into a three-dimensional network with hexa­gonal channels running parallel to the c axis. The silver cation, located in the channel, is bonded to seven O atoms of the [InP₂O₇] framework with Ag–O distances ranging from 2.370 (2) to 3.015 (2) Å. The P₂O₇ diphosphate anion is characterized by a P—O—P angle of 137.27 (9) and a nearly eclipsed conformation. AgInP₂O₇ is isotypic with the M^IFeP₂O₇ (M^I = Na, K, Rb, Cs and Ag) diphosphate family.

Related literature

For properties of M^IFeP₂O₇ (M^I = Na, K, Rb, Cs and Ag) diphosphates, see: Terebilenko et al. (2010); Hizhnyi et al. (2008); Whangbo et al. (2004); Vitins et al. (2000). For isotypic structures, see: Belkouch et al. (1995); Gabelica-Robert et al. (1982); Moya-Pizarro et al. (1984); Mercader et al. (1990).

Experimental

Crystal data

• AgInP₂O₇

• M_r = 396.63

• Monoclinic, P 2₁ /c

• a = 7.4867 (3) Å

• b = 8.2620 (3) Å

• c = 9.8383 (5) Å

• β = 112.038 (2)°

• V = 564.09 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 8.11 mm⁻¹

• T = 296 K

• 0.08 × 0.06 × 0.05 mm

Data collection

• Bruker X8 APEXII CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 1999) T_min = 0.563, T_max = 0.667

• 21692 measured reflections

• 3730 independent reflections

• 3245 reflections with I > 2σ(I)

• R_int = 0.035

Refinement

• R[F² > 2σ(F²)] = 0.021

• wR(F²) = 0.048

• S = 1.03

• 3730 reflections

• 101 parameters

• Δρ_max = 1.62 e Å⁻³

• Δρ_min = −2.04 e Å⁻³

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); 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); software used to prepare material for publication: WinGX (Farrugia, 1999).

Supporting information

S1. Comment

The diphosphates A^IM^IIIP₂O₇ (A^I = Li, Na, K, Rb, Cs and Ag; M^III = Al, Ga, Cr, Fe, In, Y) are extensively studied for their electrical and optical properties and for its perspective application as magnetic materials (Terebilenko et al. (2010); Hizhnyi et al. (2008); Whangbo et al. (2004); Vitins et al. (2000)). The crystal structures of most of these compounds are known except a few cases in which the crystal growth is difficult. In this context, the present paper reports on the determination of AgInP₂O₇ crystal structure from X-ray diffraction single-crystal data.

The structure of this phosphate is characterized by a three-dimensional network built up from indum octahedra linked to diphosphate groups by a corner-sharing. Each InO₆ octahedra is surrounded by six PO₄ tetrahedra belonging to five different P₂O₇ groups (see Fig.1 and Fig.2). As a result of these blocks, assemblage three-dimensional-framework is formed with hexagonal channels, where silver cations reside. Although, the coordination sphere of Ag⁺ cations is composed of seven O^2- anions in an irregular geometry, located at Ag–O distances between 2.370 (2) and 3.015 (2) Å (see Fig.2). Furthermore, the diphosphate group contains two distorted PO₄ tetrahedra sharing one corner and display a nearly eclipsed conformation. The P–O bond-lengths range between 1.492 (2) Å for terminal P1–O1 and 1.606 (2) Å for the bridging P2–O7 bond. Therefore, a P1–O7–P2 angle of 137.27 (9) ° is wider than 133.6 (3)° and 132.9 (3) ° reported for both AgFeP₂O₇ and NaFeP₂O₇ respectively (Belkouch et al. (1995); Gabelica-Robert et al. (1982); Moya-Pizarro et al. (1984); Mercader et al. (1990)).

Silver indium diphosphate (pyrophosphate) is isostructural to A^IFeP₂O₇ (A^I = Na, K, Rb, Cs and Ag) diphosphates family and is categorized as a dichromate type.

Related literature

For properties of M^IFeP₂O₇ (M^I = Na, K, Rb, Cs and Ag) diphosphates, see: Terebilenko et al. (2010); Hizhnyi et al. (2008); Whangbo et al. (2004); Vitins et al. (2000). For isotypic structures, see: Belkouch et al. (1995); Gabelica-Robert et al. (1982); Moya-Pizarro et al. (1984); Mercader et al. (1990).

S2. Experimental

AgInP₂O₇ in the form of single crystals was prepared by stoichiometric reaction of AgNO₃, (NH₄)₂HPO₄ and In₂O₃ in B₂O₃ flux. The mixture was heated at 773 K under ambiante atmosphere for 6 h and 973 K for 2 h with intermediate grindings to ensure complete reaction. Subsequent melting at 1323 K followed by slow cooling to room temperature at a rate of 12°K h^-1 resulted in colourless crystals of the title compound.

S3. Refinement

The highest and deepest hole residual peak in the final difference Fourier map are located at 0.49 Å and 0.58 Å, respectively from Ag1 atom. The not significants bonds and angles were removed from the CIF file.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (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); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures

	Fig. 1. Partial plot of AgInP2O7 crystal structure shawing plyhedra linkage. Displacement ellipsoids are drawn at the 50% probability level. Symmetry codes: (i) -x + 1, y - 1/2, -z + 1/2; (ii) -x, y - 1/2, -z + 1/2; (iii) -x + 1, -y + 1, -z + 1; (iv) x, -y + 3/2, z - 1/2; (v) x - 1, y, z; (vi) x - 1, -y + 3/2, z - 1/2; (vii) -x, -y + 1, -z + 1.
	Fig. 2. Perspective view along [101] of the AgInP2O7 framework structure shawing tunnel where silver cations are located.

Silver indium diphosphate

Crystal data

AgInP2O7	F(000) = 728
Mr = 396.63	Dx = 4.670 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 317 reflections
a = 7.4867 (3) Å	θ = 2.5–30.2°
b = 8.2620 (3) Å	µ = 8.11 mm^−1
c = 9.8383 (5) Å	T = 296 K
β = 112.038 (2)°	Block, colourless
V = 564.09 (4) Å^3	0.08 × 0.06 × 0.05 mm
Z = 4

Data collection

Bruker X8 APEXII CCD area-detector diffractometer	3730 independent reflections
Radiation source: fine-focus sealed tube	3245 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ω and φ scans	θmax = 41.0°, θmin = 2.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1999)	h = −13→13
Tmin = 0.563, Tmax = 0.667	k = −15→15
21692 measured reflections	l = −18→18

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.021	w = 1/[σ^2(Fo^2) + (0.017P)^2 + 0.9979P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.048	(Δ/σ)max = 0.001
S = 1.03	Δρmax = 1.62 e Å^−3
3730 reflections	Δρmin = −2.04 e Å^−3
101 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0171 (4)

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 (Ų)

	x	y	z	Uiso*/Ueq
In1	0.242354 (15)	0.495357 (12)	0.247622 (11)	0.00618 (3)
Ag1	−0.20911 (3)	0.52697 (2)	0.30478 (2)	0.02442 (4)
P1	0.57689 (6)	0.74758 (5)	0.46083 (4)	0.00600 (6)
P2	0.17589 (6)	0.78735 (5)	0.45174 (4)	0.00656 (6)
O1	0.6810 (2)	0.86792 (17)	0.40464 (15)	0.0141 (2)
O2	0.6836 (2)	0.71622 (16)	0.62241 (14)	0.0136 (2)
O3	0.52473 (17)	0.59259 (15)	0.36935 (14)	0.01027 (19)
O4	0.04427 (18)	0.91166 (17)	0.35059 (15)	0.0123 (2)
O5	0.1917 (2)	0.79561 (16)	0.60976 (14)	0.0126 (2)
O6	0.13231 (18)	0.61348 (15)	0.39564 (14)	0.01054 (19)
O7	0.37868 (18)	0.83601 (16)	0.44239 (16)	0.0128 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
In1	0.00656 (4)	0.00614 (4)	0.00593 (4)	−0.00024 (3)	0.00244 (3)	−0.00045 (3)
Ag1	0.01913 (7)	0.02720 (8)	0.03341 (9)	−0.00235 (6)	0.01725 (7)	−0.01071 (7)
P1	0.00574 (14)	0.00643 (14)	0.00582 (14)	−0.00025 (11)	0.00217 (11)	0.00044 (11)
P2	0.00588 (14)	0.00706 (14)	0.00644 (14)	0.00073 (11)	0.00195 (11)	−0.00090 (12)
O1	0.0185 (6)	0.0141 (5)	0.0133 (5)	−0.0053 (4)	0.0104 (5)	0.0012 (4)
O2	0.0195 (6)	0.0098 (5)	0.0070 (4)	−0.0006 (4)	−0.0001 (4)	0.0018 (4)
O3	0.0072 (4)	0.0099 (5)	0.0130 (5)	−0.0012 (3)	0.0030 (4)	−0.0040 (4)
O4	0.0084 (5)	0.0135 (5)	0.0135 (5)	0.0034 (4)	0.0023 (4)	0.0041 (4)
O5	0.0211 (6)	0.0099 (5)	0.0072 (4)	−0.0009 (4)	0.0058 (4)	−0.0023 (4)
O6	0.0116 (5)	0.0097 (5)	0.0123 (5)	−0.0019 (4)	0.0067 (4)	−0.0039 (4)
O7	0.0078 (5)	0.0100 (5)	0.0217 (6)	0.0010 (4)	0.0069 (4)	−0.0020 (4)

Geometric parameters (Å, º)

In1—O1^i	2.0799 (13)	Ag1—O5^vii	2.7829 (14)
In1—O4^ii	2.1120 (12)	Ag1—O6^vii	3.0153 (14)
In1—O2^iii	2.1133 (13)	P1—O1	1.4919 (13)
In1—O5^iv	2.1401 (13)	P1—O2	1.5097 (13)
In1—O3	2.1562 (12)	P1—O3	1.5292 (13)
In1—O6	2.1569 (12)	P1—O7	1.6021 (13)
Ag1—O3^v	2.3703 (12)	P2—O4	1.5101 (13)
Ag1—O6	2.4757 (13)	P2—O5	1.5158 (13)
Ag1—O4^ii	2.4865 (14)	P2—O6	1.5295 (13)
Ag1—O2^vi	2.6991 (14)	P2—O7	1.6062 (13)
Ag1—O7^ii	2.7744 (15)
O1^i—In1—O4^ii	90.70 (6)	O3^v—Ag1—O5^vii	94.99 (4)
O1^i—In1—O2^iii	86.35 (6)	O6—Ag1—O5^vii	104.03 (4)
O4^ii—In1—O2^iii	89.82 (6)	O4^ii—Ag1—O5^vii	80.85 (4)
O1^i—In1—O5^iv	89.04 (5)	O2^vi—Ag1—O5^vii	157.25 (4)
O4^ii—In1—O5^iv	93.79 (5)	O7^ii—Ag1—O5^vii	71.00 (4)
O2^iii—In1—O5^iv	174.18 (6)	O3^v—Ag1—O6^vii	72.37 (4)
O1^i—In1—O3	96.36 (5)	O6—Ag1—O6^vii	88.04 (4)
O4^ii—In1—O3	172.86 (5)	O4^ii—Ag1—O6^vii	119.79 (4)
O2^iii—In1—O3	89.55 (5)	O2^vi—Ag1—O6^vii	148.46 (4)
O5^iv—In1—O3	87.43 (5)	O7^ii—Ag1—O6^vii	119.64 (4)
O1^i—In1—O6	173.56 (5)	O5^vii—Ag1—O6^vii	50.65 (4)
O4^ii—In1—O6	82.94 (5)	O1—P1—O2	111.17 (8)
O2^iii—In1—O6	92.62 (5)	O1—P1—O3	113.17 (8)
O5^iv—In1—O6	92.35 (5)	O2—P1—O3	113.16 (8)
O3—In1—O6	89.98 (5)	O1—P1—O7	104.17 (8)
O3^v—Ag1—O6	134.04 (4)	O2—P1—O7	107.40 (8)
O3^v—Ag1—O4^ii	155.99 (4)	O3—P1—O7	107.10 (7)
O6—Ag1—O4^ii	69.47 (4)	O4—P2—O5	115.20 (8)
O3^v—Ag1—O2^vi	85.86 (5)	O4—P2—O6	113.76 (8)
O6—Ag1—O2^vi	91.29 (4)	O5—P2—O6	109.65 (8)
O4^ii—Ag1—O2^vi	89.15 (5)	O4—P2—O7	100.90 (8)
O3^v—Ag1—O7^ii	102.17 (4)	O5—P2—O7	109.63 (8)
O6—Ag1—O7^ii	123.47 (4)	O6—P2—O7	107.01 (7)
O4^ii—Ag1—O7^ii	54.04 (4)	P1—O7—P2	137.27 (9)
O2^vi—Ag1—O7^ii	86.57 (4)

Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x, y−1/2, −z+1/2; (iii) −x+1, −y+1, −z+1; (iv) x, −y+3/2, z−1/2; (v) x−1, y, z; (vi) x−1, −y+3/2, z−1/2; (vii) −x, −y+1, −z+1.

 

Footnotes

‡Permanent address: Centre National pour la Recherche Scientifique et Technique, Division UATRS, Angle Allal AlFassi et Avenue des FAR, Hay Ryad, BP 8027, Rabat, Morocco.