Poly[diaqua-tetra-μ-seleno-cyanato-cadmium(II)dipotassium(I)].

In the title compound, [CdK(2)(NCSe)(4)(H(2)O)(2)](n), the cadmium(II) cation is situated on a twofold rotation axis and is coordinated in a slightly distorted tetra-hedral geometry by two symmetry-related μ-1,1,1,3 and two-symmetry related μ-1,1,3,3 bridging seleno-cyanate anions, all of which are Se bonded. These bridging seleno-cyanate anions are further coordinated to two symmetry-related potassium ions. Each of the potassium ions is coordinated by one terminally bonded water mol-ecule and six seleno-cyanate anions, two of which are crystallographically independent. The asymmetric unit consists of one cadmium and one potassium cation, two bridging seleno-cyanate anions and one water mol-ecule. The polymeric subunits are further connected via the seleno-cyanate anions into a three-dimensional coordination network. In this coordination network, intramolecular hydrogen bonds between neighbouring water molecules can be found.

Related literature

For general background to transition metal thio- and seleno­cyanates and N-donor ligands, see: Näther et al. (2007 ▶); Bhosekar et al. (2006 ▶); Wriedt & Näther (2010 ▶); Wriedt et al. (2010a ▶,b ▶). For related structures, see: Shi et al. (2007 ▶); Couhorn & Dronskowski (2004 ▶). For similar coordination modes in azido anions, see: El Fallah et al. (2008 ▶); Guo & Mak (1998 ▶).

Experimental

Crystal data

[CdK2(NCSe)4(H2O)2]

M = 646.55

Monoclinic,

a = 21.574 (3) Å

b = 4.4055 (4) Å

c = 17.9316 (19) Å

β = 112.454 (13)°

V = 1575.1 (3) Å3

Z = 4

Mo Kα radiation

μ = 11.15 mm−1

T = 170 K

0.05 × 0.04 × 0.03 mm

Data collection

Stoe IPDS-1 diffractometer

Absorption correction: numerical (X-SHAPE and X-RED32; Stoe & Cie, 2008 ▶) T min = 0.588, T max = 0.713

4687 measured reflections

1800 independent reflections

1355 reflections with I > 2σ(I)

R int = 0.057

Refinement

R[F 2 > 2σ(F 2)] = 0.037

wR(F 2) = 0.090

S = 1.00

1800 reflections

79 parameters

H-atom parameters constrained

Δρmax = 0.90 e Å−3

Δρmin = −0.94 e Å−3

Data collection: X-AREA (Stoe & Cie, 2008 ▶); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810034938/fj2330sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810034938/fj2330Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[CdK2(NCSe)4(H2O)2]	F(000) = 1176
Mr = 646.55	Dx = 2.726 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 4533 reflections
a = 21.574 (3) Å	θ = 2.5–27.5°
b = 4.4055 (4) Å	µ = 11.15 mm−1
c = 17.9316 (19) Å	T = 170 K
β = 112.454 (13)°	Block, colourless
V = 1575.1 (3) Å3	0.05 × 0.04 × 0.03 mm
Z = 4

Stoe IPDS-1 diffractometer	1800 independent reflections
Radiation source: fine-focus sealed tube	1355 reflections with I > 2σ(I)
graphite	Rint = 0.057
φ Scans scans	θmax = 27.5°, θmin = 2.5°
Absorption correction: numerical (X-SHAPE and X-RED32; Stoe & Cie, 2008)	h = −28→26
Tmin = 0.588, Tmax = 0.713	k = −5→4
4687 measured reflections	l = −23→23

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)] = 0.037	H-atom parameters constrained
wR(F2) = 0.090	w = 1/[σ2(Fo2) + (0.052P)2] where P = (Fo2 + 2Fc2)/3
S = 1.00	(Δ/σ)max = 0.001
1800 reflections	Δρmax = 0.90 e Å−3
79 parameters	Δρmin = −0.94 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00083 (16)

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
Cd1	0.5000	0.53865 (16)	0.7500	0.02159 (19)
Se1	0.39046 (3)	0.19271 (15)	0.71167 (3)	0.02260 (18)
C1	0.3440 (3)	0.3582 (16)	0.6125 (4)	0.0257 (13)
N1	0.3131 (3)	0.4620 (16)	0.5497 (3)	0.0320 (13)
Se2	0.49070 (3)	0.85366 (16)	0.61994 (3)	0.02357 (19)
C2	0.5606 (4)	0.6741 (17)	0.6015 (4)	0.0293 (15)
N2	0.6047 (4)	0.5706 (16)	0.5900 (4)	0.0381 (15)
K1	0.32739 (8)	0.9210 (4)	0.44900 (8)	0.0291 (3)
O1	0.2416 (3)	0.8171 (13)	0.2915 (3)	0.0375 (12)
H1	0.1999	0.8495	0.2786	0.056*
H2	0.2463	0.6824	0.2602	0.056*

	U11	U22	U33	U12	U13	U23
Cd1	0.0190 (3)	0.0260 (4)	0.0195 (3)	0.000	0.0071 (2)	0.000
Se1	0.0206 (3)	0.0229 (3)	0.0237 (3)	−0.0014 (2)	0.0078 (2)	0.0018 (2)
C1	0.022 (3)	0.026 (4)	0.033 (3)	−0.006 (3)	0.015 (3)	−0.004 (3)
N1	0.028 (3)	0.037 (4)	0.028 (3)	−0.003 (3)	0.007 (2)	0.002 (3)
Se2	0.0244 (3)	0.0258 (4)	0.0208 (3)	0.0022 (3)	0.0089 (2)	0.0020 (2)
C2	0.038 (4)	0.029 (4)	0.022 (3)	−0.004 (3)	0.013 (3)	−0.002 (3)
N2	0.047 (4)	0.033 (4)	0.048 (3)	0.008 (3)	0.033 (3)	0.002 (3)
K1	0.0348 (8)	0.0263 (8)	0.0292 (7)	0.0001 (6)	0.0155 (6)	−0.0005 (6)
O1	0.032 (3)	0.042 (3)	0.039 (3)	−0.007 (3)	0.015 (2)	−0.008 (2)

Cd1—Se2	2.6548 (7)	Se2—C2	1.841 (7)
Cd1—Se1	2.6720 (8)	C2—N2	1.143 (10)
Se1—C1	1.827 (7)	N2—K1iii	2.847 (7)
C1—N1	1.161 (9)	N2—K1iv	2.904 (7)
N1—K1	2.806 (6)	K1—O1	2.760 (5)
N1—K1i	3.076 (7)	O1—H1	0.8501
N1—K1ii	3.083 (7)	O1—H2	0.8500
Se2—Cd1—Se2v	116.97 (4)	N1vi—K1—N1ii	63.1 (2)
Se2—Cd1—Se1	108.03 (2)	O1—K1—Se2	152.89 (13)
Se2v—Cd1—Se1	106.66 (2)	N1—K1—Se2	73.29 (13)
Se2—Cd1—Se1v	106.66 (2)	N2iii—K1—Se2	74.08 (15)
Se2v—Cd1—Se1v	108.03 (2)	N2iv—K1—Se2	81.55 (15)
Se1—Cd1—Se1v	110.45 (4)	N1vi—K1—Se2	81.53 (12)
C1—Se1—Cd1	97.2 (2)	N1ii—K1—Se2	129.50 (11)
N1—C1—Se1	178.5 (6)	O1—K1—K1vi	99.55 (13)
C1—N1—K1	138.2 (5)	N1—K1—K1vi	136.11 (14)
C1—N1—K1i	96.6 (5)	N2iii—K1—K1vi	139.52 (14)
K1—N1—K1i	96.89 (17)	N2iv—K1—K1vi	39.54 (13)
C1—N1—K1ii	105.1 (5)	N1vi—K1—K1vi	39.22 (12)
K1—N1—K1ii	103.6 (2)	N1ii—K1—K1vi	80.38 (13)
K1i—N1—K1ii	116.9 (2)	Se2—K1—K1vi	94.61 (3)
C2—Se2—Cd1	98.1 (2)	O1—K1—K1i	80.45 (13)
C2—Se2—K1	118.2 (2)	N1—K1—K1i	43.89 (14)
Cd1—Se2—K1	119.93 (3)	N2iii—K1—K1i	40.48 (14)
N2—C2—Se2	178.1 (7)	N2iv—K1—K1i	140.46 (13)
C2—N2—K1iii	152.8 (6)	N1vi—K1—K1i	140.78 (12)
C2—N2—K1iv	105.5 (6)	N1ii—K1—K1i	99.62 (13)
K1iii—N2—K1iv	99.98 (19)	Se2—K1—K1i	85.39 (3)
O1—K1—N1	110.08 (18)	K1vi—K1—K1i	180.00 (9)
O1—K1—N2iii	80.18 (19)	O1—K1—K1ii	92.68 (12)
N1—K1—N2iii	78.66 (19)	N1—K1—K1ii	40.35 (13)
O1—K1—N2iv	94.85 (19)	N2iii—K1—K1ii	111.46 (15)
N1—K1—N2iv	154.22 (19)	N2iv—K1—K1ii	148.48 (14)
N2iii—K1—N2iv	99.98 (19)	N1vi—K1—K1ii	76.76 (12)
O1—K1—N1vi	123.42 (18)	N1ii—K1—K1ii	36.10 (12)
N1—K1—N1vi	96.89 (17)	Se2—K1—K1ii	104.44 (5)
N2iii—K1—N1vi	155.49 (19)	K1vi—K1—K1ii	108.99 (4)
N2iv—K1—N1vi	73.55 (17)	K1i—K1—K1ii	71.01 (4)
O1—K1—N1ii	75.99 (16)	K1—O1—H1	118.5
N1—K1—N1ii	76.4 (2)	K1—O1—H2	126.1
N2iii—K1—N1ii	136.7 (2)	H1—O1—H2	108.6
N2iv—K1—N1ii	117.42 (19)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H2···O1vii	0.85	1.92	2.760 (6)	167

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H2⋯O1i	0.85	1.92	2.760 (6)	167

Symmetry code: (i) .