Crystal structure of CdSO₄(H₂O): a redetermination

Abstract

The crystal structure of the title compound, cadmium sulfate monohydrate or poly[(μ₂-aqua)(μ₄-sulfato)­cadmium], was redetermined based on modern CMOS (complementary metal oxide silicon) data. In comparison with the previous study [Bregeault & Herpin (1970 ▸). Bull. Soc. Fr. Mineral. Cristallogr. 93, 37–42], all non-H atoms were refined with anisotropic displacement parameters and the hydrogen-bonding pattern unambiguously established due to location of the hydrogen atoms. In addition, a significant improvement in terms of precision and accuracy was achieved. In the crystal, the Cd²⁺ cation is coordinated by four O atoms of four sulfate anions and two O atoms of water mol­ecules, forming a distorted octa­hedral trans-[CdO₆] polyhedron. Each sulfate anion bridges four Cd²⁺ cations and each water mol­ecule bridges two Cd²⁺ cations, leading to the formation of a three-dimensional framework, with Cd⋯Cd separations in the range 4.0757 (2)–6.4462 (3) Å. O—H⋯O hydrogen-bonding inter­actions of medium strength between the coordinating water mol­ecules and sulfate anions consolidate the crystal packing.

Related literature  

For the previous report on the structure of the title compound, see: Bregeault & Herpin (1970 ▸).

Experimental  

Crystal data  

• CdSO₄(H₂O)

• M _r = 226.48

• Monoclinic,

• a = 7.6195 (3) Å

• b = 7.4517 (3) Å

• c = 8.1457 (3) Å

• β = 122.244 (1)°

• V = 391.17 (3) ų

• Z = 4

• Mo Kα radiation

• μ = 6.01 mm⁻¹

• T = 296 K

• 0.26 × 0.22 × 0.22 mm

Data collection  

• Bruker APEXII D8 QUEST CMOS diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2014 ▸) T _min = 0.701, T _max = 0.746

• 17459 measured reflections

• 1004 independent reflections

• 958 reflections with I > 2σ(I)

• R _int = 0.023

Refinement  

• R[F ² > 2σ(F ²)] = 0.012

• wR(F ²) = 0.026

• S = 1.18

• 1004 reflections

• 72 parameters

• 2 restraints

• All H-atom parameters refined

• Δρ_max = 0.29 e Å⁻³

• Δρ_min = −0.33 e Å⁻³

Data collection: APEX2 (Bruker, 2014 ▸); cell refinement: SAINT (Bruker, 2014 ▸); data reduction: SAINT; method used to solve structure: coordinates taken from previous refinement; program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015 ▸); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▸); software used to prepare material for publication: OLEX2 and publCIF (Westrip, 2010 ▸).

Supplementary Material

CCDC reference: 1423357

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
O5H5AO3i	0.82(2)	1.88(2)	2.6958(17)	170(3)
O5H5BO2ii	0.86(2)	1.90(2)	2.7530(17)	173(2)

Symmetry codes: (i) ; (ii) .

Table 2. Comparison of bond lengths () in the current and the previous (Bregeault Herpin, 1970 ▸) refinement of cadmium sulfate monohydrate.

For the previous refinement: a = 7.607, b = 7.541, c = 8.186, = 121.86 and reliability index R = 0.12.

Bond	Current refinement	Previous refinement
Cd1O1i	2.2417(12)	2.21(5)
Cd1O2ii	2.2530(13)	2.27(3)
Cd1O3	2.2421(12)	2.36(5)
Cd1O4iii	2.3112(12)	2.33(3)
Cd1O5i	2.3210(12)	2.24(3)
Cd1O5	2.4024(12)	2.33(3)
S1O1	1.4703(12)	1.50(4)
S1O2	1.4845(12)	1.62(6)
S1O3	1.4831(12)	1.45(3)
S1O4	1.4584(12)	1.42(4)

Symmetry codes: (i) x, y+, z+; (ii) x, y+1, z; (iii) x+1, y , z+.

supplementary crystallographic information

S1. Synthesis and crystallization

The title compound was obtained serendipitously. CdSO₄·8/3H₂O (0.256 g, 1 mmol) and 3,6-di-2-pyridyl-1,2,4,5-tetra­zine (0.236 g, 1 mmol) dissolved in water (5 ml) were added to a 23 ml Teflon-lined autoclave and heated at 356 K for 5 days. The product was collected by filtration, washed with water and air-dried. Colourless block-shaped crystals of the title compound suitable for X-ray analysis were isolated.

S2. Refinement

The same cell setting and atom numbering scheme as in the previous refinement (Bregeault & Herpin, 1970) were used. Starting coordinates for the atoms were also taken from the previous model. Hydrogen atoms of the water molecules were located from difference Fourier maps and were refined with an O—H distance restraint of 0.85 (2) Å.

Figures

Fig. 1.

The coordination sphere around the Cd2+ cation with displacement ellipsoids drawn at the 50% probability level. [Symmetry codes: (i) x, 1/2 – y, 1/2 + z; (ii) –x, 1 – y, –z; (iii) 1 – x, -1/2 + y, 1/2 – z].

Fig. 2.

The three-dimensional framework structure of the title compound in a view along the b axis. Dashed lines indicate intermolecular O—H···O hydrogen-bonding interactions.

Crystal data

CdSO4(H2O)	F(000) = 424
Mr = 226.48	Dx = 3.846 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.6195 (3) Å	Cell parameters from 9894 reflections
b = 7.4517 (3) Å	θ = 3.2–30.5°
c = 8.1457 (3) Å	µ = 6.01 mm−1
β = 122.244 (1)°	T = 296 K
V = 391.17 (3) Å3	Block, colourless
Z = 4	0.26 × 0.22 × 0.22 mm

Data collection

Bruker APEXII D8 QUEST CMOS diffractometer	1004 independent reflections
Radiation source: microfocus sealed x-ray tube, Incoatec Iµus	958 reflections with I > 2σ(I)
GraphiteDouble Bounce Multilayer Mirror monochromator	Rint = 0.023
Detector resolution: 10.5 pixels mm-1	θmax = 28.7°, θmin = 3.2°
ω and φ scans	h = −10→10
Absorption correction: multi-scan (SADABS; Bruker, 2014)	k = −10→10
Tmin = 0.701, Tmax = 0.746	l = −10→10
17459 measured reflections

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.012	All H-atom parameters refined
wR(F2) = 0.026	w = 1/[σ2(Fo2) + (0.0107P)2 + 0.2955P] where P = (Fo2 + 2Fc2)/3
S = 1.18	(Δ/σ)max = 0.001
1004 reflections	Δρmax = 0.28 e Å−3
72 parameters	Δρmin = −0.33 e Å−3
2 restraints

Special details

Experimental. SADABS was used for absorption correction. wR2(int) was 0.0449 before and 0.0357 after correction. The Ratio of minimum to maximum transmission is 0.9396. The λ/2 correction factor is 0.00150.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cd1	0.21887 (2)	0.26013 (2)	0.26053 (2)	0.01330 (5)
S1	0.25524 (6)	0.61729 (5)	0.01217 (5)	0.01018 (8)
O1	0.13754 (18)	0.50022 (16)	−0.15811 (17)	0.0183 (2)
O2	0.1103 (2)	0.75977 (15)	−0.00480 (19)	0.0169 (3)
O3	0.32756 (18)	0.51255 (16)	0.19211 (17)	0.0168 (2)
O4	0.43393 (18)	0.69973 (18)	0.02148 (18)	0.0184 (2)
O5	0.27603 (19)	0.09752 (16)	0.03844 (17)	0.0140 (2)
H5A	0.400 (3)	0.074 (4)	0.110 (3)	0.038 (7)*
H5B	0.216 (3)	−0.005 (2)	0.016 (3)	0.023 (6)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cd1	0.01176 (7)	0.01373 (7)	0.01200 (7)	−0.00165 (4)	0.00472 (5)	0.00087 (4)
S1	0.00809 (16)	0.00898 (17)	0.01063 (17)	0.00001 (13)	0.00310 (14)	0.00041 (13)
O1	0.0156 (6)	0.0170 (6)	0.0158 (6)	−0.0004 (5)	0.0041 (5)	−0.0054 (5)
O2	0.0122 (6)	0.0134 (6)	0.0206 (6)	0.0027 (4)	0.0058 (5)	−0.0018 (4)
O3	0.0155 (6)	0.0153 (6)	0.0147 (5)	−0.0019 (5)	0.0048 (5)	0.0046 (4)
O4	0.0101 (5)	0.0224 (6)	0.0198 (6)	−0.0022 (5)	0.0061 (5)	0.0047 (5)
O5	0.0120 (5)	0.0133 (5)	0.0145 (5)	−0.0008 (4)	0.0055 (5)	−0.0001 (4)

Geometric parameters (Å, º)

Cd1—O1i	2.2417 (12)	S1—O3	1.4831 (12)
Cd1—O2ii	2.2530 (13)	S1—O4	1.4584 (12)
Cd1—O3	2.2421 (12)	O1—Cd1iv	2.2417 (12)
Cd1—O4iii	2.3112 (12)	O2—Cd1ii	2.2530 (13)
Cd1—O5i	2.3210 (12)	O4—Cd1v	2.3112 (12)
Cd1—O5	2.4024 (12)	O5—Cd1iv	2.3211 (12)
S1—O1	1.4703 (12)	O5—H5A	0.822 (17)
S1—O2	1.4845 (12)	O5—H5B	0.859 (16)
O1i—Cd1—O2ii	82.50 (4)	O1—S1—O3	109.76 (7)
O1i—Cd1—O3	175.24 (4)	O3—S1—O2	109.52 (8)
O1i—Cd1—O4iii	89.31 (5)	O4—S1—O1	112.43 (8)
O1i—Cd1—O5i	92.57 (4)	O4—S1—O2	109.35 (7)
O1i—Cd1—O5	88.62 (4)	O4—S1—O3	109.03 (7)
O2ii—Cd1—O4iii	161.94 (4)	S1—O1—Cd1iv	131.81 (7)
O2ii—Cd1—O5	80.22 (4)	S1—O2—Cd1ii	116.42 (7)
O2ii—Cd1—O5i	117.97 (4)	S1—O3—Cd1	134.06 (7)
O3—Cd1—O2ii	101.65 (4)	S1—O4—Cd1v	140.91 (8)
O3—Cd1—O4iii	86.05 (4)	Cd1iv—O5—Cd1	119.27 (5)
O3—Cd1—O5	89.80 (4)	Cd1iv—O5—H5A	109.7 (18)
O3—Cd1—O5i	87.54 (4)	Cd1—O5—H5A	99.9 (18)
O4iii—Cd1—O5i	78.31 (4)	Cd1iv—O5—H5B	113.3 (14)
O4iii—Cd1—O5	83.53 (4)	Cd1—O5—H5B	108.6 (14)
O5i—Cd1—O5	161.78 (6)	H5A—O5—H5B	104 (2)
O1—S1—O2	106.70 (7)
O1—S1—O2—Cd1ii	2.46 (10)	O3—S1—O1—Cd1iv	−54.81 (11)
O1—S1—O3—Cd1	−23.82 (12)	O3—S1—O2—Cd1ii	−116.29 (8)
O1—S1—O4—Cd1v	−135.57 (12)	O3—S1—O4—Cd1v	−13.61 (15)
O2—S1—O1—Cd1iv	−173.39 (9)	O4—S1—O1—Cd1iv	66.74 (12)
O2—S1—O3—Cd1	93.01 (11)	O4—S1—O2—Cd1ii	124.30 (8)
O2—S1—O4—Cd1v	106.10 (13)	O4—S1—O3—Cd1	−147.38 (10)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O3iii	0.82 (2)	1.88 (2)	2.6958 (17)	170 (3)
O5—H5B···O2vi	0.86 (2)	1.90 (2)	2.7530 (17)	173 (2)

Symmetry codes: (iii) −x+1, y−1/2, −z+1/2; (vi) x, y−1, z.