Tricaesium tetra­selenidoarsenate(V) monohydrate

The title compound, Cs₃AsSe₄·H₂O, contains discrete tetra­hedral tetra­selenidoarsenate(V) anions. The solvent water O atom participates in the coordination spheres of all three independent Cs cations, as do, in each case, seven Se atoms.

Key indicators

• Single-crystal X-ray study
• T = 292 K
• Mean [sigma](e-As) = 0.004 Å
• H-atom completeness 1%
• R factor = 0.068
• wR factor = 0.201
• Data-to-parameter ratio = 27.7

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT306_ALERT_2_A Isolated Oxygen Atom (H-atoms Missing ?) .......          O

Author Response: The water H atoms could not be located in the final difference synthesis and were not, therefore, included in the refinement.

Alert level C
PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings    Differ ....          ?

Author Response: The water H atoms could not be located in the final difference synthesis and were not, therefore, included in the refinement.

PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?

Author Response: The water H atoms could not be located in the final difference synthesis and were not, therefore, included in the refinement.

PLAT068_ALERT_1_C Reported F000 Differs from Calcd (or Missing)...          ?

Author Response: The water H atoms could not be located in the final difference synthesis and were not, therefore, included in the refinement.

Alert level G
FORMU01_ALERT_2_G  There is a discrepancy between the atom counts in the
            _chemical_formula_sum and the formula from the _atom_site* data.
            Atom count from _chemical_formula_sum:H2 As1 Cs3 O1 Se4
            Atom count from the _atom_site data:  As1 Cs3 O1 Se4
CELLZ01_ALERT_1_G Difference between formula and atom_site contents detected.
CELLZ01_ALERT_1_G WARNING: H atoms missing from atom site list. Is this intentional?
           From the CIF: _cell_formula_units_Z    4
           From the CIF: _chemical_formula_sum  As Cs3 H2 O Se4
           TEST: Compare cell contents of formula and atom_site data

           atom    Z*formula  cif sites diff
           As         4.00      4.00    0.00
           Cs        12.00     12.00    0.00
           H          8.00      0.00    8.00
           O          4.00      4.00    0.00
           Se        16.00     16.00    0.00

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

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

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Computing details

Data collection: R3m/V (Siemens, 1989); cell refinement: R3m/V; data reduction: XDISK (Siemens, 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1995); software used to prepare material for publication: SHELXL97.

Tricaesium tetraselenidoarsenate(V) monohydrate

Crystal data

Cs3AsSe4·H2O	F(000) = 1376
Mr = 807.51	Dx = 4.117 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 18 reflections
a = 9.994 (3) Å	θ = 5.5–12.7°
b = 10.541 (4) Å	µ = 22.00 mm^−1
c = 12.372 (6) Å	T = 292 K
β = 91.73 (2)°	Block, red
V = 1302.8 (9) Å^3	0.15 × 0.13 × 0.11 mm
Z = 4

Data collection

Siemens P4 four-circle diffractometer	1399 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.046
Graphite monochromator	θmax = 25.0°, θmin = 2.5°
ω scans	h = 0→11
Absorption correction: ψ scan (XPREP in SHELXTL; Sheldrick, 1995)	k = −12→0
Tmin = 0.054, Tmax = 0.092	l = −14→14
2449 measured reflections	3 standard reflections every 97 reflections
2295 independent reflections	intensity decay: 0.1%

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)] = 0.068	H-atom parameters not refined
wR(F^2) = 0.201	w = 1/[σ^2(Fo^2) + (0.0949P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.15	(Δ/σ)max < 0.001
2295 reflections	Δρmax = 1.95 e Å^−3
83 parameters	Δρmin = −2.41 e Å^−3
0 restraints

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
Cs1	0.90925 (18)	0.84281 (18)	0.21561 (13)	0.0415 (5)
Cs2	0.28972 (18)	1.01905 (17)	0.45224 (12)	0.0388 (5)
Cs3	0.32259 (18)	1.06435 (17)	0.05415 (13)	0.0412 (5)
Se1	0.2577 (3)	0.7863 (3)	0.2325 (2)	0.0343 (7)
Se2	0.5801 (3)	0.9712 (3)	0.2622 (2)	0.0344 (7)
As	0.4864 (2)	0.7707 (2)	0.26577 (17)	0.0253 (6)
Se3	0.5292 (3)	0.6767 (3)	0.4324 (2)	0.0403 (7)
Se4	0.5753 (3)	0.6496 (3)	0.1301 (2)	0.0438 (8)
O	0.378 (2)	0.783 (2)	−0.0614 (16)	0.058 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cs1	0.0355 (10)	0.0511 (11)	0.0379 (8)	0.0058 (9)	0.0011 (7)	−0.0016 (8)
Cs2	0.0458 (11)	0.0370 (10)	0.0339 (8)	−0.0006 (8)	0.0036 (7)	−0.0011 (7)
Cs3	0.0432 (11)	0.0425 (10)	0.0379 (9)	0.0106 (9)	0.0027 (7)	0.0011 (8)
Se1	0.0236 (13)	0.0402 (16)	0.0388 (14)	−0.0019 (12)	−0.0034 (10)	−0.0022 (12)
Se2	0.0336 (16)	0.0277 (14)	0.0418 (14)	−0.0060 (12)	0.0017 (11)	0.0011 (11)
As	0.0246 (13)	0.0268 (13)	0.0245 (11)	0.0032 (11)	0.0006 (9)	0.0028 (10)
Se3	0.0386 (16)	0.0531 (19)	0.0291 (12)	−0.0015 (14)	−0.0034 (11)	0.0122 (12)
Se4	0.0525 (19)	0.0425 (17)	0.0370 (14)	0.0099 (15)	0.0132 (12)	−0.0046 (13)
O	0.076 (16)	0.041 (13)	0.057 (12)	−0.010 (12)	0.008 (11)	−0.007 (10)

Geometric parameters (Å, º)

Cs1—O^i	3.09 (2)	Cs2—Se4^vi	4.002 (4)
Cs1—Se1^ii	3.533 (3)	Cs3—O	3.34 (2)
Cs1—Se2	3.620 (3)	Cs3—O^ix	3.39 (2)
Cs1—Se3^iii	3.743 (3)	Cs3—Se1^vi	3.635 (3)
Cs1—Se4^iv	3.756 (4)	Cs3—Se2	3.717 (3)
Cs1—Se2^v	3.928 (4)	Cs3—Se3^vi	3.718 (3)
Cs1—Se3^iv	4.024 (4)	Cs3—Se1	3.737 (3)
Cs1—Se4	4.024 (4)	Cs3—Se4^ix	3.933 (4)
Cs2—O^vi	3.54 (2)	Cs3—Se2^ix	4.079 (3)
Cs2—Se4^vii	3.588 (3)	Cs3—Se3^x	4.130 (4)
Cs2—Se1^vi	3.650 (3)	As—Se4	2.308 (4)
Cs2—Se1	3.668 (3)	As—Se2	2.313 (4)
Cs2—Se2^viii	3.729 (3)	As—Se3	2.316 (3)
Cs2—Se2	3.822 (3)	As—Se1	2.316 (4)
Cs2—Se3^viii	3.929 (4)
O^vi—Cs2—Se4^vii	81.8 (3)	Se2—Cs3—Se3^vi	133.55 (7)
O^vi—Cs2—Se1^vi	65.0 (3)	O—Cs3—Se1	65.9 (4)
Se4^vii—Cs2—Se1^vi	134.25 (9)	O^ix—Cs3—Se1	121.6 (4)
O^vi—Cs2—Se1	141.0 (4)	Se1^vi—Cs3—Se1	91.72 (5)
Se4^vii—Cs2—Se1	94.74 (8)	Se2—Cs3—Se1	60.84 (6)
Se1^vi—Cs2—Se1	92.60 (5)	Se3^vi—Cs3—Se1	92.42 (8)
O^vi—Cs2—Se2^viii	76.9 (3)	O—Cs3—Se4^ix	112.5 (4)
Se4^vii—Cs2—Se2^viii	68.32 (7)	O^ix—Cs3—Se4^ix	53.8 (4)
Se1^vi—Cs2—Se2^viii	127.38 (8)	Se1^vi—Cs3—Se4^ix	89.66 (8)
Se1—Cs2—Se2^viii	137.77 (8)	Se2—Cs3—Se4^ix	114.69 (8)
O^vi—Cs2—Se2	135.7 (4)	Se3^vi—Cs3—Se4^ix	92.51 (8)
Se4^vii—Cs2—Se2	142.20 (8)	Se1—Cs3—Se4^ix	174.96 (8)
Se1^vi—Cs2—Se2	78.65 (7)	O—Cs3—Cs3^ix	53.5 (4)
Se1—Cs2—Se2	60.47 (6)	O^ix—Cs3—Cs3^ix	52.3 (4)
Se2^viii—Cs2—Se2	109.66 (7)	O—Cs3—Se2^ix	57.4 (4)
O^vi—Cs2—Se3^viii	55.8 (4)	O^ix—Cs3—Se2^ix	80.4 (3)
Se4^vii—Cs2—Se3^viii	117.30 (8)	Se1^vi—Cs3—Se2^ix	145.11 (8)
Se1^vi—Cs2—Se3^viii	69.33 (7)	Se2—Cs3—Se2^ix	117.40 (6)
Se1—Cs2—Se3^viii	147.55 (8)	Se3^vi—Cs3—Se2^ix	108.99 (7)
Se2^viii—Cs2—Se3^viii	59.33 (6)	Se1—Cs3—Se2^ix	123.04 (7)
Se2—Cs2—Se3^viii	88.91 (7)	Se4^ix—Cs3—Se2^ix	56.00 (6)
O^vi—Cs2—Se4^vi	52.3 (4)	Cs3^ix—Cs3—Se2^ix	54.33 (6)
Se4^vii—Cs2—Se4^vi	76.69 (8)	O—Cs3—Se3^x	54.8 (4)
Se1^vi—Cs2—Se4^vi	58.34 (6)	O^ix—Cs3—Se3^x	156.4 (3)
Se1—Cs2—Se4^vi	89.02 (7)	Se1^vi—Cs3—Se3^x	119.41 (7)
Se2^viii—Cs2—Se4^vi	121.40 (7)	Se2—Cs3—Se3^x	124.00 (8)
Se2—Cs2—Se4^vi	126.30 (7)	Se3^vi—Cs3—Se3^x	63.28 (8)
Se3^viii—Cs2—Se4^vi	102.60 (7)	Se1—Cs3—Se3^x	66.35 (7)
O^vi—Cs2—As	166.5 (3)	Se4^ix—Cs3—Se3^x	117.01 (8)
Se4^vii—Cs2—As	109.82 (8)	Cs3^ix—Cs3—Se3^x	106.95 (8)
Se1^vi—Cs2—As	101.46 (7)	Se2^ix—Cs3—Se3^x	77.34 (6)
Se1—Cs2—As	34.55 (6)	Cs1^ix—Cs3—Se3^x	58.36 (6)
Se2^viii—Cs2—As	113.39 (7)	O—Cs3—As	64.0 (4)
Se2—Cs2—As	34.08 (6)	O^ix—Cs3—As	90.3 (4)
Se3^viii—Cs2—As	120.64 (7)	Se1^vi—Cs3—As	96.23 (7)
Se4^vi—Cs2—As	122.22 (7)	Se2—Cs3—As	32.17 (6)
Se4—As—Se2	109.08 (14)	Se3^vi—Cs3—As	122.68 (7)
Se4—As—Se3	110.24 (15)	Se1—Cs3—As	32.22 (5)
Se2—As—Se3	110.12 (14)	Se4^ix—Cs3—As	142.77 (7)
Se4—As—Se1	108.04 (14)	Cs3^ix—Cs3—As	69.14 (6)
Se2—As—Se1	109.26 (14)	Se2^ix—Cs3—As	114.62 (7)
Se3—As—Se1	110.07 (13)	Cs1^ix—Cs3—As	148.18 (7)
Se4—As—Cs2	168.14 (12)	Se3^x—Cs3—As	91.83 (7)
Se2—As—Cs2	67.83 (9)	As—Se1—Cs1^xii	171.20 (12)
Se3—As—Cs2	81.30 (10)	As—Se1—Cs3^xi	93.65 (10)
Se1—As—Cs2	63.94 (9)	Cs1^xii—Se1—Cs3^xi	85.00 (7)
Se4—As—Cs3	95.87 (10)	As—Se1—Cs2^xi	99.51 (11)
Se2—As—Cs3	58.85 (9)	Cs1^xii—Se1—Cs2^xi	89.08 (7)
Se3—As—Cs3	153.89 (12)	Cs3^xi—Se1—Cs2^xi	86.01 (8)
Se1—As—Cs3	59.36 (9)	As—Se1—Cs2	81.50 (10)
Cs2—As—Cs3	72.62 (6)	Cs1^xii—Se1—Cs2	89.71 (7)
Se4—As—Cs1	66.20 (10)	Cs3^xi—Se1—Cs2	84.76 (7)
Se2—As—Cs1	56.15 (9)	Cs2^xi—Se1—Cs2	170.77 (9)
Se3—As—Cs1	92.73 (10)	As—Se1—Cs3	88.42 (10)
Se1—As—Cs1	156.74 (11)	Cs1^xii—Se1—Cs3	91.21 (7)
Cs2—As—Cs1	117.34 (7)	Cs3^xi—Se1—Cs3	168.42 (9)
Cs3—As—Cs1	98.02 (6)	Cs2^xi—Se1—Cs3	104.90 (8)
Cs1^x—O—Cs3	141.9 (7)	Cs2—Se1—Cs3	84.28 (8)
Cs1^x—O—Cs3^ix	96.6 (6)	As—Se2—Cs1	91.81 (11)
Cs3—O—Cs3^ix	74.2 (4)	As—Se2—Cs3	88.98 (10)
Cs1^x—O—Cs2^xi	93.6 (5)	Cs1—Se2—Cs3	127.01 (8)
Cs3—O—Cs2^xi	116.6 (6)	As—Se2—Cs2^viii	97.88 (10)
Cs3^ix—O—Cs2^xi	142.1 (7)	Cs1—Se2—Cs2^viii	82.44 (7)
O^i—Cs1—Se1^ii	90.0 (4)	Cs3—Se2—Cs2^viii	149.71 (9)
O^i—Cs1—Se2	84.4 (4)	As—Se2—Cs2	78.09 (9)
Se1^ii—Cs1—Se2	162.28 (8)	Cs1—Se2—Cs2	149.07 (8)
O^i—Cs1—Se3^iii	148.9 (4)	Cs3—Se2—Cs2	82.45 (7)
Se1^ii—Cs1—Se3^iii	72.74 (7)	Cs2^viii—Se2—Cs2	70.34 (7)
Se2—Cs1—Se3^iii	119.21 (8)	As—Se2—Cs1^iv	156.97 (13)
O^i—Cs1—Se4^iv	85.5 (4)	Cs1—Se2—Cs1^iv	111.17 (7)
Se1^ii—Cs1—Se4^iv	95.15 (8)	Cs3—Se2—Cs1^iv	78.56 (7)
Se2—Cs1—Se4^iv	67.70 (7)	Cs2^viii—Se2—Cs1^iv	84.18 (6)
Se3^iii—Cs1—Se4^iv	120.91 (8)	Cs2—Se2—Cs1^iv	81.09 (6)
O^i—Cs1—Se2^v	60.7 (4)	As—Se2—Cs3^ix	92.43 (10)
Se1^ii—Cs1—Se2^v	78.64 (7)	Cs1—Se2—Cs3^ix	64.43 (6)
Se2—Cs1—Se2^v	112.63 (7)	Cs3—Se2—Cs3^ix	62.60 (6)
Se3^iii—Cs1—Se2^v	90.09 (7)	Cs2^viii—Se2—Cs3^ix	145.60 (9)
Se4^iv—Cs1—Se2^v	145.34 (7)	Cs2—Se2—Cs3^ix	144.06 (8)
O^i—Cs1—Se3^iv	143.6 (4)	Cs1^iv—Se2—Cs3^ix	98.74 (7)
Se1^ii—Cs1—Se3^iv	90.60 (7)	As—Se3—Cs3^xi	91.53 (10)
Se2—Cs1—Se3^iv	84.12 (7)	As—Se3—Cs1^vii	143.25 (13)
Se3^iii—Cs1—Se3^iv	64.17 (8)	Cs3^xi—Se3—Cs1^vii	67.09 (6)
Se4^iv—Cs1—Se3^iv	58.24 (7)	As—Se3—Cs2^viii	92.56 (11)
Se2^v—Cs1—Se3^iv	154.15 (7)	Cs3^xi—Se3—Cs2^viii	132.03 (9)
O^i—Cs1—Se4	84.9 (4)	Cs1^vii—Se3—Cs2^viii	82.07 (7)
Se1^ii—Cs1—Se4	137.60 (8)	As—Se3—Cs1^v	89.76 (11)
Se2—Cs1—Se4	58.71 (7)	Cs3^xi—Se3—Cs1^v	84.23 (7)
Se3^iii—Cs1—Se4	90.72 (7)	Cs1^vii—Se3—Cs1^v	115.83 (8)
Se4^iv—Cs1—Se4	126.19 (6)	Cs2^viii—Se3—Cs1^v	143.53 (9)
Se2^v—Cs1—Se4	62.23 (7)	As—Se3—Cs3^i	134.27 (12)
Se3^iv—Cs1—Se4	117.39 (7)	Cs3^xi—Se3—Cs3^i	116.72 (8)
O^i—Cs1—As	70.9 (4)	Cs1^vii—Se3—Cs3^i	82.46 (6)
Se1^ii—Cs1—As	157.04 (8)	Cs2^viii—Se3—Cs3^i	93.19 (7)
Se2—Cs1—As	32.04 (6)	Cs1^v—Se3—Cs3^i	60.73 (6)
Se3^iii—Cs1—As	117.59 (7)	As—Se4—Cs2^iii	165.95 (14)
Se4^iv—Cs1—As	95.90 (7)	As—Se4—Cs1^v	96.75 (11)
Se2^v—Cs1—As	80.83 (6)	Cs2^iii—Se4—Cs1^v	82.47 (8)
Se3^iv—Cs1—As	112.32 (7)	As—Se4—Cs3^ix	96.29 (12)
Se4—Cs1—As	31.66 (5)	Cs2^iii—Se4—Cs3^ix	81.63 (7)
Cs3^ix—Cs1—As	68.46 (5)	Cs1^v—Se4—Cs3^ix	161.31 (9)
O—Cs3—O^ix	105.8 (4)	As—Se4—Cs2^xi	90.41 (11)
O—Cs3—Se1^vi	157.5 (4)	Cs2^iii—Se4—Cs2^xi	103.31 (8)
O^ix—Cs3—Se1^vi	83.7 (3)	Cs1^v—Se4—Cs2^xi	81.74 (7)
O—Cs3—Se2	86.7 (4)	Cs3^ix—Se4—Cs2^xi	111.50 (8)
O^ix—Cs3—Se2	61.0 (4)	As—Se4—Cs1	82.14 (11)
Se1^vi—Cs3—Se2	80.24 (7)	Cs2^iii—Se4—Cs1	84.62 (8)
O—Cs3—Se3^vi	118.1 (4)	Cs1^v—Se4—Cs1	106.33 (8)
O^ix—Cs3—Se3^vi	133.0 (4)	Cs3^ix—Se4—Cs1	62.40 (6)
Se1^vi—Cs3—Se3^vi	62.15 (6)	Cs2^xi—Se4—Cs1	169.54 (9)

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