cis-Bis(4-methyl­piperazine-1-carbo­dithio­ato-κ2S,S′)bis­(pyridine-κN)cadmium

Valarmathi, P.; Thirumaran, S.; Kapoor, K.; Gupta, V.K.; Kant, R.

doi:10.1107/S1600536811054791

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 1| January 2012| Page m89

doi:10.1107/S1600536811054791

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cis-Bis(4-methylpiperazine-1-carbodithioato-κ²S,S′)bis(pyridine-κN)cadmium

P. Valarmathi,^a S. Thirumaran,^a Kamini Kapoor,^b Vivek K. Gupta ^b and Rajni Kant ^b ^*

^aDepartment of Chemistry, Annamalai University, Annamalainagar 608 002, India, and ^bX-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics, University of Jammu, Jammu Tawi 180 006, India
^*Correspondence e-mail: rkvk.paper11@gmail.com

(Received 25 November 2011; accepted 20 December 2011; online 23 December 2011)

In the title complex, [Cd(C₆H₁₁N₂S₂)₂(C₅H₅N)₂], the Cd^II ion is hexacoordinated by two N atoms from two pyridine ligands and by four S atoms from two dithiocarbamate ligands in a distorted octahedral geometry. The Cd^II ion lies on a twofold axis. The piperazine ring is in chair conformation and its least-squares plane makes a dihedral angle of 81.4 (1)° with that of the pyridine ring.

Related literature

For background to and applications of dithiocarbamates, see: Bessergenev et al. (1997 ); Havel (1975 ); Valarmathi et al. (2011 ); Pickett & O'Brien (2001 ). For related structures, see: Ivanov et al. (2006 ); Onwudiwe & Ajibade (2010 ); Yin et al. (2004 ).

Experimental

Crystal data

[Cd(C₆H₁₁N₂S₂)₂(C₅H₅N)₂]
M_r = 621.18
Monoclinic, C 2/c
a = 17.7065 (7) Å
b = 8.7806 (6) Å
c = 20.6171 (8) Å
β = 122.276 (5)°
V = 2710.1 (2) Å³
Z = 4
Mo Kα radiation
μ = 1.14 mm⁻¹
T = 293 K
0.3 × 0.2 × 0.2 mm

Data collection

Oxford Diffraction Xcalibur Sapphire3 diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.645, T_max = 1.000
24135 measured reflections
2383 independent reflections
2088 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.057
S = 1.07
2383 reflections
151 parameters
H-atom parameters constrained
Δρ_max = 0.40 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis RED (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: PLATON (Spek, 2009 ) and PARST (Nardelli, 1995 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811054791/nc2258sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811054791/nc2258Isup2.hkl

checkCIF report

Comment top

The use of nitrogen donor adducts of cadmium dithiocarbamate complexes as convenient synthetic precursors for cadmium sulfide nanoparticles (Bessergenev et al., 1997; Havel, 1975, Pickett & O'Brien 2001; Valarmathi et al., 2011), attract continued attention to adducts of cadmium dithiocarbamates. As part of an on-going structural studies of nitrogen donor adducts of cadmium dithiocarbamates, the analysis of the title compound, (I), was undertaken. The bond angles around the cadmium atom are in the range of 67.56 (2) to 171.50 (3)°. The Cd—S bond lengths are: CD1—S1 = 2.6621 (7); CD1—S2 = to 2.6803 (7) Å and are in good agreement with those reported for other Cd- dithiocarbonato complexes (Ivanov et al., 2006; Onwudiwe et al., 2010; Yin et al., 2004). The piperazine ring has a chair conformation. The asymmetry parameters are: ΔCs(N2)=0.72; ΔC2(N2—C3)= 0.73. The dihedral angle between the best least squares planes through piperazine and pyridine rings is 81.4 (1)°.

Related literature top

For background to and applications of dithiocarbamates, see: Bessergenev et al. (1997); Havel (1975); Valarmathi et al. (2011); Pickett & O'Brien (2001). For related structures, see: Ivanov et al. (2006); Onwudiwe et al. (2010); Yin et al. (2004).

Experimental top

Cd(4-mpzdtc)₂] (1 mmol, 0.483 g) was dissolved in 50 ml of warm pyridine. The yellow solution obtained was filtered and kept for evaporation. After few days, single crystals suitable for X-ray structural analysis were obtained (m.p. 552–554 K).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis RED (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009) and PARST (Nardelli, 1995).

Figures top

Fig. 1. ORTEP view of the molecule with the atom-labeling scheme. The thermal ellipsoids are drawn at the 40% probability level. H atoms are shown as small spheres of arbitrary radii. Symmetry code = -x, y, -z + 1/2.

cis-Bis(4-methylpiperazine-1-carbodithioato- κ²S,S')bis(pyridine-κN)cadmium top

Crystal data top

[Cd(C₆H₁₁N₂S₂)₂(C₅H₅N)₂]	F(000) = 1272
M_r = 621.18	D_x = 1.522 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 11642 reflections
a = 17.7065 (7) Å	θ = 3.5–29.1°
b = 8.7806 (6) Å	µ = 1.14 mm⁻¹
c = 20.6171 (8) Å	T = 293 K
β = 122.276 (5)°	Block, white
V = 2710.1 (2) Å³	0.3 × 0.2 × 0.2 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur Sapphire3 diffractometer	2383 independent reflections
Radiation source: fine-focus sealed tube	2088 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
Detector resolution: 16.1049 pixels mm^-1	θ_max = 25.0°, θ_min = 3.8°
ω scans	h = −20→20
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2010)	k = −10→10
T_min = 0.645, T_max = 1.000	l = −24→24
24135 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.057	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0157P)² + 4.0129P] where P = (F_o² + 2F_c²)/3
2383 reflections	(Δ/σ)_max < 0.001
151 parameters	Δρ_max = 0.40 e Å⁻³
0 restraints	Δρ_min = −0.30 e Å⁻³

Crystal data top

[Cd(C₆H₁₁N₂S₂)₂(C₅H₅N)₂]	V = 2710.1 (2) Å³
M_r = 621.18	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 17.7065 (7) Å	µ = 1.14 mm⁻¹
b = 8.7806 (6) Å	T = 293 K
c = 20.6171 (8) Å	0.3 × 0.2 × 0.2 mm
β = 122.276 (5)°

Data collection top

Oxford Diffraction Xcalibur Sapphire3 diffractometer	2383 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2010)	2088 reflections with I > 2σ(I)
T_min = 0.645, T_max = 1.000	R_int = 0.047
24135 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.026	0 restraints
wR(F²) = 0.057	H-atom parameters constrained
S = 1.07	Δρ_max = 0.40 e Å⁻³
2383 reflections	Δρ_min = −0.30 e Å⁻³
151 parameters

Special details top

Experimental. CrysAlis PRO, Oxford Diffraction Ltd., Version 1.171.34.40 (release 27–08-2010 CrysAlis171. NET) (compiled Aug 27 2010,11:50:40) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cd1	0.0000	0.14900 (3)	0.2500	0.04703 (10)
S1	0.08961 (5)	0.12653 (8)	0.17998 (4)	0.05259 (19)
S2	−0.07368 (5)	−0.05272 (9)	0.13462 (4)	0.0550 (2)
C1	0.01848 (16)	−0.0220 (3)	0.12909 (13)	0.0415 (6)
N2	0.03409 (14)	−0.1100 (3)	0.08483 (12)	0.0472 (5)
C3	−0.01499 (18)	−0.2496 (3)	0.04814 (16)	0.0552 (7)
H3A	−0.0316	−0.2518	−0.0049	0.066*
H3B	−0.0692	−0.2532	0.0490	0.066*
C4	0.04322 (18)	−0.3850 (3)	0.09059 (16)	0.0537 (7)
H4A	0.0569	−0.3849	0.1428	0.064*
H4B	0.0109	−0.4780	0.0660	0.064*
N5	0.12635 (14)	−0.3821 (3)	0.09173 (12)	0.0486 (5)
C6	0.17350 (18)	−0.2393 (3)	0.12557 (16)	0.0535 (7)
H6A	0.2272	−0.2361	0.1239	0.064*
H6B	0.1913	−0.2354	0.1789	0.064*
C7	0.11636 (19)	−0.1028 (3)	0.08401 (17)	0.0552 (7)
H7A	0.1487	−0.0101	0.1089	0.066*
H7B	0.1018	−0.1019	0.0315	0.066*
C8	0.1830 (2)	−0.5113 (4)	0.13378 (18)	0.0658 (8)
H8A	0.2363	−0.5078	0.1323	0.099*
H8B	0.1514	−0.6042	0.1107	0.099*
H8C	0.1988	−0.5070	0.1861	0.099*
N9	−0.09469 (14)	0.3546 (3)	0.16984 (11)	0.0476 (5)
C10	−0.13114 (18)	0.3577 (4)	0.09431 (15)	0.0561 (7)
H10	−0.1166	0.2808	0.0718	0.067*
C11	−0.1891 (2)	0.4693 (4)	0.04841 (17)	0.0701 (9)
H11	−0.2141	0.4665	−0.0043	0.084*
C12	−0.2098 (2)	0.5841 (4)	0.0804 (2)	0.0707 (9)
H12	−0.2492	0.6608	0.0501	0.085*
C13	−0.1715 (2)	0.5845 (4)	0.1582 (2)	0.0702 (9)
H13	−0.1833	0.6625	0.1821	0.084*
C14	−0.1153 (2)	0.4675 (4)	0.20016 (17)	0.0625 (8)
H14	−0.0902	0.4674	0.2529	0.075*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.05092 (17)	0.05401 (19)	0.03837 (15)	0.000	0.02532 (13)	0.000
S1	0.0537 (4)	0.0546 (4)	0.0574 (4)	−0.0160 (3)	0.0350 (4)	−0.0129 (3)
S2	0.0477 (4)	0.0652 (5)	0.0606 (4)	−0.0153 (3)	0.0346 (4)	−0.0175 (4)
C1	0.0434 (14)	0.0443 (15)	0.0351 (13)	0.0004 (12)	0.0198 (11)	0.0044 (11)
N2	0.0480 (12)	0.0535 (14)	0.0487 (12)	−0.0072 (10)	0.0317 (11)	−0.0095 (10)
C3	0.0494 (16)	0.066 (2)	0.0482 (16)	−0.0072 (14)	0.0247 (14)	−0.0184 (14)
C4	0.0593 (17)	0.0576 (18)	0.0497 (16)	−0.0190 (14)	0.0330 (14)	−0.0141 (13)
N5	0.0534 (13)	0.0503 (14)	0.0459 (12)	−0.0031 (11)	0.0291 (11)	−0.0021 (10)
C6	0.0502 (16)	0.0602 (18)	0.0599 (17)	−0.0077 (14)	0.0360 (14)	−0.0033 (15)
C7	0.0668 (18)	0.0536 (17)	0.0679 (19)	−0.0057 (14)	0.0511 (16)	−0.0017 (14)
C8	0.0697 (19)	0.060 (2)	0.0642 (19)	0.0003 (16)	0.0330 (16)	0.0036 (16)
N9	0.0469 (12)	0.0577 (14)	0.0362 (11)	0.0016 (11)	0.0208 (10)	−0.0025 (11)
C10	0.0576 (17)	0.072 (2)	0.0430 (15)	−0.0001 (16)	0.0295 (14)	−0.0007 (15)
C11	0.065 (2)	0.096 (3)	0.0455 (17)	0.0059 (19)	0.0269 (16)	0.0226 (18)
C12	0.0588 (19)	0.072 (2)	0.081 (2)	0.0091 (17)	0.0365 (18)	0.034 (2)
C13	0.078 (2)	0.0545 (19)	0.080 (2)	0.0082 (17)	0.0436 (19)	0.0018 (17)
C14	0.071 (2)	0.063 (2)	0.0449 (16)	0.0074 (16)	0.0251 (15)	−0.0054 (15)

Geometric parameters (Å, º) top

Cd1—N9ⁱ	2.417 (2)	C6—C7	1.506 (4)
Cd1—N9	2.417 (2)	C6—H6A	0.9700
Cd1—S1ⁱ	2.6621 (7)	C6—H6B	0.9700
Cd1—S1	2.6621 (7)	C7—H7A	0.9700
Cd1—S2	2.6803 (7)	C7—H7B	0.9700
Cd1—S2ⁱ	2.6803 (7)	C8—H8A	0.9600
S1—C1	1.725 (3)	C8—H8B	0.9600
S2—C1	1.717 (2)	C8—H8C	0.9600
C1—N2	1.333 (3)	N9—C14	1.323 (3)
N2—C3	1.459 (3)	N9—C10	1.330 (3)
N2—C7	1.467 (3)	C10—C11	1.368 (4)
C3—C4	1.510 (4)	C10—H10	0.9300
C3—H3A	0.9700	C11—C12	1.359 (5)
C3—H3B	0.9700	C11—H11	0.9300
C4—N5	1.460 (3)	C12—C13	1.368 (4)
C4—H4A	0.9700	C12—H12	0.9300
C4—H4B	0.9700	C13—C14	1.369 (4)
N5—C8	1.455 (4)	C13—H13	0.9300
N5—C6	1.460 (3)	C14—H14	0.9300

N9ⁱ—Cd1—N9	83.36 (10)	C4—N5—C6	109.7 (2)
N9ⁱ—Cd1—S1ⁱ	94.66 (5)	N5—C6—C7	111.9 (2)
N9—Cd1—S1ⁱ	91.69 (5)	N5—C6—H6A	109.2
N9ⁱ—Cd1—S1	91.69 (5)	C7—C6—H6A	109.2
N9—Cd1—S1	94.66 (5)	N5—C6—H6B	109.2
S1ⁱ—Cd1—S1	171.50 (3)	C7—C6—H6B	109.2
N9ⁱ—Cd1—S2	158.69 (5)	H6A—C6—H6B	107.9
N9—Cd1—S2	93.18 (5)	N2—C7—C6	109.2 (2)
S1ⁱ—Cd1—S2	106.48 (2)	N2—C7—H7A	109.8
S1—Cd1—S2	67.56 (2)	C6—C7—H7A	109.8
N9ⁱ—Cd1—S2ⁱ	93.18 (5)	N2—C7—H7B	109.8
N9—Cd1—S2ⁱ	158.69 (5)	C6—C7—H7B	109.8
S1ⁱ—Cd1—S2ⁱ	67.56 (2)	H7A—C7—H7B	108.3
S1—Cd1—S2ⁱ	106.48 (2)	N5—C8—H8A	109.5
S2—Cd1—S2ⁱ	97.27 (4)	N5—C8—H8B	109.5
C1—S1—Cd1	86.15 (8)	H8A—C8—H8B	109.5
C1—S2—Cd1	85.73 (9)	N5—C8—H8C	109.5
N2—C1—S2	120.42 (19)	H8A—C8—H8C	109.5
N2—C1—S1	120.25 (18)	H8B—C8—H8C	109.5
S2—C1—S1	119.31 (15)	C14—N9—C10	117.0 (2)
C1—N2—C3	123.9 (2)	C14—N9—Cd1	120.15 (18)
C1—N2—C7	123.6 (2)	C10—N9—Cd1	122.80 (19)
C3—N2—C7	110.5 (2)	N9—C10—C11	122.7 (3)
N2—C3—C4	109.1 (2)	N9—C10—H10	118.6
N2—C3—H3A	109.9	C11—C10—H10	118.6
C4—C3—H3A	109.9	C12—C11—C10	119.5 (3)
N2—C3—H3B	109.9	C12—C11—H11	120.2
C4—C3—H3B	109.9	C10—C11—H11	120.2
H3A—C3—H3B	108.3	C11—C12—C13	118.5 (3)
N5—C4—C3	111.5 (2)	C11—C12—H12	120.7
N5—C4—H4A	109.3	C13—C12—H12	120.7
C3—C4—H4A	109.3	C12—C13—C14	118.5 (3)
N5—C4—H4B	109.3	C12—C13—H13	120.8
C3—C4—H4B	109.3	C14—C13—H13	120.8
H4A—C4—H4B	108.0	N9—C14—C13	123.7 (3)
C8—N5—C4	111.4 (2)	N9—C14—H14	118.2
C8—N5—C6	110.4 (2)	C13—C14—H14	118.2

N9ⁱ—Cd1—S1—C1	178.45 (10)	C8—N5—C6—C7	−179.3 (2)
N9—Cd1—S1—C1	−98.07 (10)	C4—N5—C6—C7	−56.2 (3)
S1ⁱ—Cd1—S1—C1	40.12 (8)	C1—N2—C7—C6	105.6 (3)
S2—Cd1—S1—C1	−6.55 (8)	C3—N2—C7—C6	−59.0 (3)
S2ⁱ—Cd1—S1—C1	84.63 (9)	N5—C6—C7—N2	57.5 (3)
N9ⁱ—Cd1—S2—C1	20.45 (18)	N9ⁱ—Cd1—N9—C14	−49.4 (2)
N9—Cd1—S2—C1	100.31 (10)	S1ⁱ—Cd1—N9—C14	45.1 (2)
S1ⁱ—Cd1—S2—C1	−166.98 (8)	S1—Cd1—N9—C14	−140.6 (2)
S1—Cd1—S2—C1	6.58 (8)	S2—Cd1—N9—C14	151.7 (2)
S2ⁱ—Cd1—S2—C1	−98.30 (9)	S2ⁱ—Cd1—N9—C14	32.3 (3)
Cd1—S2—C1—N2	170.5 (2)	N9ⁱ—Cd1—N9—C10	133.4 (2)
Cd1—S2—C1—S1	−10.81 (13)	S1ⁱ—Cd1—N9—C10	−132.1 (2)
Cd1—S1—C1—N2	−170.4 (2)	S1—Cd1—N9—C10	42.2 (2)
Cd1—S1—C1—S2	10.87 (14)	S2—Cd1—N9—C10	−25.5 (2)
S2—C1—N2—C3	−9.9 (3)	S2ⁱ—Cd1—N9—C10	−144.91 (17)
S1—C1—N2—C3	171.4 (2)	C14—N9—C10—C11	−1.4 (4)
S2—C1—N2—C7	−172.5 (2)	Cd1—N9—C10—C11	175.9 (2)
S1—C1—N2—C7	8.8 (3)	N9—C10—C11—C12	1.2 (5)
C1—N2—C3—C4	−105.1 (3)	C10—C11—C12—C13	0.2 (5)
C7—N2—C3—C4	59.5 (3)	C11—C12—C13—C14	−1.3 (5)
N2—C3—C4—N5	−58.5 (3)	C10—N9—C14—C13	0.3 (4)
C3—C4—N5—C8	179.0 (2)	Cd1—N9—C14—C13	−177.1 (2)
C3—C4—N5—C6	56.5 (3)	C12—C13—C14—N9	1.1 (5)

Symmetry code: (i) −x, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Cd(C₆H₁₁N₂S₂)₂(C₅H₅N)₂]
M_r	621.18
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	17.7065 (7), 8.7806 (6), 20.6171 (8)
β (°)	122.276 (5)
V (Å³)	2710.1 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.14
Crystal size (mm)	0.3 × 0.2 × 0.2

Data collection
Diffractometer	Oxford Diffraction Xcalibur Sapphire3 diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2010)
T_min, T_max	0.645, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	24135, 2383, 2088
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.026, 0.057, 1.07
No. of reflections	2383
No. of parameters	151
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.30

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), CrysAlis RED (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2009) and PARST (Nardelli, 1995).

Acknowledgements

RK acknowledges the Department of Science & Technology for the diffractometer sanctioned as a National Facility under project No. SR/S2/CMP-47/2003. He is also thankful to the University of Jammu, Jammu, for financial support.

References

Bessergenev, V. G., Ivanova, E. N., Kovalevskaya, Y. A., Vasilieva, I. G., Varand, V. L., Zemskova, S. M., Larinov, S. V., Kolesov, B. A., Ayupov, B. M. & Logvinenko, V. A. (1997). Thin Solid Films, 32, 1403–1410. CAS Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Havel, H. J. (1975). Semiconductors/Semimetals, Solar Cells, Vol. 11, New York: Academic Press. Google Scholar
Ivanov, A. V., Gerasimenko, A. V., Konzelko, A. A., Ivanov, M. A., Antzutkin, O. N. & Forsling, W. (2006). Inorg. Chim. Acta, 359, 3855–3864. Web of Science CSD CrossRef CAS Google Scholar
Nardelli, M. (1995). J. Appl. Cryst. 28, 659. CrossRef IUCr Journals Google Scholar
Onwudiwe, D. C. & Ajibade, P. A. (2010). Polyhedron, 29, 1431–1436. Web of Science CSD CrossRef CAS Google Scholar
Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England. Google Scholar
Pickett, N. L. & O'Brien, P. (2001). Chem. Rec. 1, 467–479. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Valarmathi, P., Thirumaran, S., Ragi, P. & Ciattini, S. (2011). J. Coord. Chem. 64, 4157–4167. Web of Science CSD CrossRef CAS Google Scholar
Yin, X., Zhang, W., Zhang, Q., Fan, J., Lai, C. S. & Tiekink, E. R. T. (2004). Appl. Organomet. Chem. 18, 139–140. Web of Science CSD CrossRef CAS Google Scholar

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