Redetermination of Ag₂[TeO₂(OH)₄]: a revised hydrogen-bonding scheme

The crystal structure of the title compound, disilver(I) tetra­hydro­dodioxotellurate(VI), has been redetermined; it confirms the previous study [Fischer (1969). Monatsh. Chem. 100, 1809–1822] which was based on film data, but with higher precision, with all displacement factors refined anisotropically for non-H atoms and with the localization of the H atoms, which leads to a different hydrogen-bonding scheme from that originally proposed. The structure of Ag₂[TeO₂(OH)₄] can be derived from a distorted hexa­gonal close packing of [TeO₂(OH)₄]²⁻ octa­hedra (Te site symmetry 2) with the Ag⁺ cations located in the inter­stices. O—H...O hydrogen bonds help to stabilize the structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](g-Ag) = 0.001 Å
• R factor = 0.033
• wR factor = 0.039
• Data-to-parameter ratio = 22.9

checkCIF/PLATON results

No syntax errors found



Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.107
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.11

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           34.92
           From the CIF: _reflns_number_total               1167
           Count of symmetry unique reflns          614
           Completeness (_total/calc)            190.07%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       553
           Fraction of Friedel pairs measured     0.901
           Are heavy atom types Z>Si present        yes
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: HELENA implemented in PLATON (Spek, 2003); program(s) used to solve structure: coordinates taken from a previous refinement; program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ATOMS (Dowty, 2006); software used to prepare material for publication: SHELXL97.

Disilver(I) tetrahydroxodioxotellurate(VI)

Crystal data

Ag2[TeO2(OH)4]	F(000) = 1584
Mr = 443.37	Dx = 5.561 Mg m^−3
Orthorhombic, Fdd2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 25 reflections
a = 18.5845 (18) Å	θ = 11.3–16.2°
b = 6.4186 (7) Å	µ = 12.75 mm^−1
c = 8.879 (1) Å	T = 293 K
V = 1059.1 (2) Å^3	Prism, light yellow
Z = 8	0.18 × 0.15 × 0.14 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	1140 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.107
Graphite monochromator	θmax = 34.9°, θmin = 4.1°
ω/2θ scans	h = −29→29
Absorption correction: numerical (HABITUS; Herrendorf, 1997)	k = −10→10
Tmin = 0.226, Tmax = 0.337	l = −14→14
4417 measured reflections	3 standard reflections every 300 min
1167 independent reflections	intensity decay: none

Refinement

Refinement on F^2	Hydrogen site location: difference Fourier map
Least-squares matrix: full	All H-atom parameters refined
R[F^2 > 2σ(F^2)] = 0.033	w = 1/[σ^2(Fo^2) + (0.0192P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.039	(Δ/σ)max = 0.001
S = 1.09	Δρmax = 1.91 e Å^−3
1167 reflections	Δρmin = −3.14 e Å^−3
51 parameters	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
3 restraints	Extinction coefficient: 0.00918 (18)
Primary atom site location: isomorphous structure methods	Absolute structure: Flack (1983), 554 Friedel pairs
Secondary atom site location: none	Absolute structure parameter: 0.22 (2)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Te	0.0000	0.0000	0.002000 (11)	0.00736 (6)
Ag	0.079916 (12)	0.52615 (4)	0.98669 (4)	0.02515 (9)
O1	0.04247 (9)	0.8207 (4)	0.8601 (2)	0.0109 (3)
O2	0.04460 (9)	0.8320 (5)	0.1599 (2)	0.0161 (4)
O3	0.08359 (8)	0.1808 (3)	0.0064 (2)	0.0130 (3)
H1	0.022 (4)	0.787 (10)	0.254 (5)	0.037 (11)*
H2	0.129 (3)	0.126 (9)	0.040 (6)	0.037 (11)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Te	0.00781 (8)	0.00498 (9)	0.00931 (8)	0.00088 (5)	0.000	0.000
Ag	0.02056 (11)	0.00880 (12)	0.04609 (18)	0.00267 (6)	0.00392 (9)	0.00486 (12)
O1	0.0108 (6)	0.0072 (10)	0.0146 (6)	0.0001 (6)	0.0029 (5)	−0.0048 (7)
O2	0.0125 (7)	0.0199 (12)	0.0159 (7)	0.0019 (7)	−0.0007 (5)	0.0099 (8)
O3	0.0087 (5)	0.0071 (8)	0.0232 (7)	−0.0014 (5)	−0.0030 (6)	0.0018 (7)

Geometric parameters (Å, º)

Te—O1^i	1.8799 (19)	Ag—Ag^iv	2.9893 (5)
Te—O1^ii	1.8799 (19)	Ag—Ag^viii	3.2110 (3)
Te—O3^iii	1.9395 (17)	Ag—Ag^ix	3.2110 (3)
Te—O3	1.9395 (17)	O1—Te^x	1.8799 (19)
Te—O2^iv	1.953 (2)	O2—Te^xi	1.953 (2)
Te—O2^v	1.953 (2)	O2—Ag^xii	2.4561 (17)
Ag—O3^vi	2.225 (2)	O2—Ag^xiii	2.579 (3)
Ag—O1	2.307 (2)	O2—H1	0.98 (4)
Ag—O2^vii	2.4561 (17)	O3—Ag^xiii	2.225 (2)
Ag—O2^vi	2.579 (3)	O3—H2	0.95 (4)
O1^i—Te—O1^ii	95.84 (13)	O2^vii—Ag—Ag^iv	163.72 (4)
O1^i—Te—O3^iii	89.06 (9)	O2^vi—Ag—Ag^iv	80.36 (4)
O1^ii—Te—O3^iii	92.49 (9)	O3^vi—Ag—Ag^viii	115.31 (5)
O1^i—Te—O3	92.49 (9)	O1—Ag—Ag^viii	94.85 (5)
O1^ii—Te—O3	89.06 (9)	O2^vii—Ag—Ag^viii	67.88 (5)
O3^iii—Te—O3	177.69 (12)	O2^vi—Ag—Ag^viii	48.71 (4)
O1^i—Te—O2^iv	175.61 (11)	Ag^iv—Ag—Ag^viii	125.079 (9)
O1^ii—Te—O2^iv	87.99 (9)	O3^vi—Ag—Ag^ix	62.64 (5)
O3^iii—Te—O2^iv	88.62 (9)	O1—Ag—Ag^ix	103.31 (4)
O3—Te—O2^iv	89.72 (9)	O2^vii—Ag—Ag^ix	52.08 (6)
O1^i—Te—O2^v	87.99 (9)	O2^vi—Ag—Ag^ix	157.75 (5)
O1^ii—Te—O2^v	175.61 (11)	Ag^iv—Ag—Ag^ix	117.545 (10)
O3^iii—Te—O2^v	89.72 (9)	Ag^viii—Ag—Ag^ix	117.084 (15)
O3—Te—O2^v	88.62 (9)	Te^x—O1—Ag	107.56 (9)
O2^iv—Te—O2^v	88.27 (14)	Te^xi—O2—Ag^xii	133.07 (10)
O3^vi—Ag—O1	149.79 (7)	Te^xi—O2—Ag^xiii	95.76 (8)
O3^vi—Ag—O2^vii	97.94 (8)	Ag^xii—O2—Ag^xiii	79.21 (7)
O1—Ag—O2^vii	91.80 (7)	Te^xi—O2—H1	127 (4)
O3^vi—Ag—O2^vi	136.02 (7)	Ag^xii—O2—H1	97 (4)
O1—Ag—O2^vi	65.78 (6)	Ag^xiii—O2—H1	113 (4)
O2^vii—Ag—O2^vi	107.23 (10)	Te—O3—Ag^xiii	124.75 (9)
O3^vi—Ag—Ag^iv	85.33 (4)	Te—O3—H2	119 (4)
O1—Ag—Ag^iv	78.01 (4)	Ag^xiii—O3—H2	115 (4)

Symmetry codes: (i) x, y−1, z−1; (ii) −x, −y+1, z−1; (iii) −x, −y, z; (iv) −x, −y+1, z; (v) x, y−1, z; (vi) x, y, z+1; (vii) −x+1/4, y−1/4, z+3/4; (viii) −x+1/4, y+1/4, z+1/4; (ix) −x+1/4, y−1/4, z−1/4; (x) x, y+1, z+1; (xi) x, y+1, z; (xii) −x+1/4, y+1/4, z−3/4; (xiii) x, y, z−1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1···O1^xiv	0.98 (4)	1.68 (4)	2.596 (2)	155 (6)
O3—H2···O1^xv	0.95 (4)	1.63 (4)	2.579 (3)	171 (6)

Symmetry codes: (xiv) −x, −y+3/2, z−1/2; (xv) −x+1/4, y−3/4, z−3/4.