metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Dicyanidobis(thio­urea-κS)cadmium(II) monohydrate

aDepartment of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia, bDepartment of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan, and cDepartment of Chemistry, University of Engineering and Technology, Lahore 54890, Pakistan
*Correspondence e-mail: saeed_a786@hotmail.com

(Received 14 July 2010; accepted 18 July 2010; online 24 July 2010)

In the title compound, [Cd(CN)2(CH4N2S)2]·H2O, the Cd atom lies on a twofold rotation axis and is bonded to two S atoms of thio­urea and two C atoms of the cyanide anions in a distorted tetra­hedral environment. The crystal structure is stabilized by N—H⋯N(CN), N—H⋯O, O—H⋯N and N—H⋯S hydrogen bonds.

Related literature

For background to cadmium(II) complexes of thio­urea-type ligands, see: Corao & Baggio (1969[Corao, E. & Baggio, S. (1969). Inorg. Chim. Acta, 3, 617-622.]); Malik et al. (2010[Malik, M. R., Ali, S., Fettouhi, M., Isab, A. A. & Ahmad, S. (2010). J. Struct. Chem. 51, 993-996.]); Marcos et al. (1998[Marcos, C., Alía, J. M., Adovasio, V., Prieto, M. & García-Granda, S. (1998). Acta Cryst. C54, 1225-1229.]); Nawaz et al. (2010a[Nawaz, S., Sadaf, S., Fettouhi, M., Fazal, A. & Ahmad, S. (2010a). Acta Cryst. E66, m950.],b[Nawaz, S., Sadaf, S., Fettouhi, M., Fazal, A. & Ahmad, S. (2010b). Acta Cryst. E66, m951.]); Wang et al. (2002[Wang, X. Q., Yu, W. T., Xu, D., Lu, M. K. & Yuan, D. R. (2002). Acta Cryst. C58, m336-m337.]). For the non-linear optical properties and semi-conducting applications of Cd–thio­urea complexes, see: Rajesh et al. (2004[Rajesh, N. P., Kannan, V., Ashok, M., Sivaji, K., Raghavan, P. S. & Ramasamy, P. (2004). J. Cryst. Growth, 262, 561-566.]); Stoev & Ruseva (1994[Stoev, M. & Ruseva, S. (1994). Monatsh. Chem. 125, 599-606.]). For the structures of cyanido complexes of d10 metal ions, see: Ahmad et al. (2009[Ahmad, S., Sadaf, H., Akkurt, M., Sharif, S. & Khan, I. U. (2009). Acta Cryst. E65, m1191-m1192.]); Hanif et al. (2007[Hanif, M., Ahmad, S., Altaf, M. & Stoeckli-Evans, H. (2007). Acta Cryst. E63, m2594.]); Yoshikawa et al. (2003[Yoshikawa, H., Nishikiori, S. & Ishida, T. (2003). J. Phys. Chem. B, 107, 9261-9267.]).

[Scheme 1]

Experimental

Crystal data
  • [Cd(CN)2(CH4N2S)2]·H2O

  • Mr = 334.70

  • Monoclinic, P 2/n

  • a = 10.5955 (6) Å

  • b = 4.0782 (3) Å

  • c = 13.4127 (8) Å

  • β = 98.738 (1)°

  • V = 572.84 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 2.25 mm−1

  • T = 294 K

  • 0.29 × 0.28 × 0.24 mm

Data collection
  • Bruker SMART APEX area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.561, Tmax = 0.614

  • 7211 measured reflections

  • 1430 independent reflections

  • 1376 reflections with I > 2σ(I)

  • Rint = 0.017

Refinement
  • R[F2 > 2σ(F2)] = 0.018

  • wR(F2) = 0.043

  • S = 1.10

  • 1430 reflections

  • 86 parameters

  • All H-atom parameters refined

  • Δρmax = 0.73 e Å−3

  • Δρmin = −0.74 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H5⋯O1i 0.72 (4) 2.26 (4) 2.961 (2) 166 (3)
N3—H4⋯S1i 0.90 (4) 2.61 (4) 3.470 (2) 159 (3)
N2—H3⋯N1ii 0.84 (3) 2.22 (3) 3.035 (2) 163 (3)
N2—H2⋯N1iii 0.78 (3) 2.51 (3) 3.286 (3) 171 (3)
O1—H1⋯N1iv 0.83 (3) 2.16 (3) 2.988 (2) 176 (3)
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x, -y, -z+1; (iii) x, y+1, z; (iv) x+1, y+1, z.

Data collection: SMART (Bruker, 2008[Bruker (2008). SMART and SAINT. Bruker AXS Inc., Madison. Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). SMART and SAINT. Bruker AXS Inc., Madison. Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

The interest in cadmium(II) complexes of thiourea (Tu) arises because some of them exhibit non-linear optical properties (Rajesh et al., 2004) and they are useful for the convenient preparation of cadmium sulfide based semiconducting materials by their thermal decomposition in air (Stoev et al., 1994). Several crystallographic reports about cadmium(II) complexes of thiourea reveal that it coordinates to cadmium(II) via the sulfur atom (Corao et al., 1969; Marcos et al., 1998; Wang et al., 2002). Recently, we have reported the crystal structures of cadmium(II) complexes of N,N'-dimethylthiourea (Dmtu), [Cd(Dmtu)2Cl2] (Malik et al., 2010) and tetramethylthiourea (Tmtu), [Cd(Tmtu)2Br2] (Nawaz et al., 2010a) and [Cd(Tmtu)2I2] (Nawaz et al., 2010b). Herein, we report the crystal structure of a cadmium cyanide complex of thiourea, biscyanidobis(thiourea-kS)cadmium(II) monohydrate, [Cd(Tu)2(CN)2].H2O. The present investigation was carried out in view of our continuous interest in the structural chemistry of cyanido complexes of d10 metal ions with thiourea type ligands (Ahmad et al., 2009; Hanif et al., 2007).

In the title compound, the Cd atom is situated on a twofold axis of symmetry and is bonded to two cyanide carbon atoms and two sulfur atoms of thiourea (Figure 1). The four coordinate metal ion adopts a severely distorted tetrahedral geometry, the bond angles being in the range of 95.76 (4) - 143.5 (1) °. The Cd—S and Cd—C bond lengths are 2.6363 (5) Å and 2.211 (2) Å respectively. These are in agreement with those reported for related compounds (Marcos et al., 1998; Malik et al. 2010; Nawaz et al., 2010a,b; Wang et al., 2002; Yoshikawa et al., 2003). The two C—N bond lengths in thiourea, C2—N2 and C2—N3, are 1.312 (2) Å and 1.305 (2) Å respectively. The CNH2 fragments of the two thiourea molecules are essentially planar, the maximum deviation from the mean plane being for the nitrogen atoms with 0.03 (1) Å. These values are consistent with a significant CN double bond character and electron delocalization in the SCN2 moiety. To the best of our knowledge, this is the first X-ray structure of a cadmium complex having both sulfur containing ligands and cyanide in its coordination sphere.

The molecules pack to form columns parallel to the b direction (Figure 2). Within these columns, each metal ion interacts with two sulfur atoms of a neighboring molecule (Cd···S: 3.3140 (5) Å), hence extending the tetra-coordinate inner-sphere to a hexa-coordinate outer-sphere with a distorted octahedral environment. These interactions confer to the molecular columns a polymeric chain character.

Intermolecular hydrogen bonding takes place through N—H···S as well as N—H···N(CN) interactions (Table 1). The complex molecules also interact with the water molecules through C—N···H—O and N—H···O bonds. In this scheme the water molecule is tetrahedrally hydrogen bonded to four complex molecules. This generates a three-dimensional hydrogen bonding network where the molecular chains are interconnected through hydrogen bonding either directly or through the water molecules.

Related literature top

For background to cadmium(II) complexes of thiourea-type ligands, see: Corao et al. (1969); Malik et al. (2010); Marcos et al. (1998); Nawaz et al. (2010a,b); Wang et al. (2002). For the non-linear optical properties and semi-conducting applications of Cd–thiourea complexes, see: Rajesh et al. (2004); Stoev et al. (1994). For the structures of cyanido complexes, see: Ahmad et al. (2009); Hanif et al. (2007); Yoshikawa et al. (2003).

Experimental top

To 0.17 g (1.0 mmol) cadmium(II) cyanide (prepared by the reaction of CdCl2.H2O and KCN in 1:2 molar ratio in water) suspended in 15 mL water was added 2 equivalents of thiourea in methanol. Yellow precipitates formed, were filtered and the filtrate was kept for crystallization. Crystals were grown by slow evaporation of a water/methanol solution at room temperature.

Refinement top

All non-H atoms were refined anisotropically. Hydrogen atoms were located in a difference Fourier map and freely refined isotropically.

Structure description top

The interest in cadmium(II) complexes of thiourea (Tu) arises because some of them exhibit non-linear optical properties (Rajesh et al., 2004) and they are useful for the convenient preparation of cadmium sulfide based semiconducting materials by their thermal decomposition in air (Stoev et al., 1994). Several crystallographic reports about cadmium(II) complexes of thiourea reveal that it coordinates to cadmium(II) via the sulfur atom (Corao et al., 1969; Marcos et al., 1998; Wang et al., 2002). Recently, we have reported the crystal structures of cadmium(II) complexes of N,N'-dimethylthiourea (Dmtu), [Cd(Dmtu)2Cl2] (Malik et al., 2010) and tetramethylthiourea (Tmtu), [Cd(Tmtu)2Br2] (Nawaz et al., 2010a) and [Cd(Tmtu)2I2] (Nawaz et al., 2010b). Herein, we report the crystal structure of a cadmium cyanide complex of thiourea, biscyanidobis(thiourea-kS)cadmium(II) monohydrate, [Cd(Tu)2(CN)2].H2O. The present investigation was carried out in view of our continuous interest in the structural chemistry of cyanido complexes of d10 metal ions with thiourea type ligands (Ahmad et al., 2009; Hanif et al., 2007).

In the title compound, the Cd atom is situated on a twofold axis of symmetry and is bonded to two cyanide carbon atoms and two sulfur atoms of thiourea (Figure 1). The four coordinate metal ion adopts a severely distorted tetrahedral geometry, the bond angles being in the range of 95.76 (4) - 143.5 (1) °. The Cd—S and Cd—C bond lengths are 2.6363 (5) Å and 2.211 (2) Å respectively. These are in agreement with those reported for related compounds (Marcos et al., 1998; Malik et al. 2010; Nawaz et al., 2010a,b; Wang et al., 2002; Yoshikawa et al., 2003). The two C—N bond lengths in thiourea, C2—N2 and C2—N3, are 1.312 (2) Å and 1.305 (2) Å respectively. The CNH2 fragments of the two thiourea molecules are essentially planar, the maximum deviation from the mean plane being for the nitrogen atoms with 0.03 (1) Å. These values are consistent with a significant CN double bond character and electron delocalization in the SCN2 moiety. To the best of our knowledge, this is the first X-ray structure of a cadmium complex having both sulfur containing ligands and cyanide in its coordination sphere.

The molecules pack to form columns parallel to the b direction (Figure 2). Within these columns, each metal ion interacts with two sulfur atoms of a neighboring molecule (Cd···S: 3.3140 (5) Å), hence extending the tetra-coordinate inner-sphere to a hexa-coordinate outer-sphere with a distorted octahedral environment. These interactions confer to the molecular columns a polymeric chain character.

Intermolecular hydrogen bonding takes place through N—H···S as well as N—H···N(CN) interactions (Table 1). The complex molecules also interact with the water molecules through C—N···H—O and N—H···O bonds. In this scheme the water molecule is tetrahedrally hydrogen bonded to four complex molecules. This generates a three-dimensional hydrogen bonding network where the molecular chains are interconnected through hydrogen bonding either directly or through the water molecules.

For background to cadmium(II) complexes of thiourea-type ligands, see: Corao et al. (1969); Malik et al. (2010); Marcos et al. (1998); Nawaz et al. (2010a,b); Wang et al. (2002). For the non-linear optical properties and semi-conducting applications of Cd–thiourea complexes, see: Rajesh et al. (2004); Stoev et al. (1994). For the structures of cyanido complexes, see: Ahmad et al. (2009); Hanif et al. (2007); Yoshikawa et al. (2003).

Computing details top

Data collection: SMART (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); 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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level (Symmetry code: i = 0.5-x, y, 0.5-z).
[Figure 2] Fig. 2. Packing diagram of the title complex showing the H-bonding interactions.
Dicyanidobis(thiourea-κS)cadmium(II) monohydrate top
Crystal data top
[Cd(CN)2(CH4N2S)2]·H2OF(000) = 328
Mr = 334.70Dx = 1.940 Mg m3
Monoclinic, P2/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yacCell parameters from 7211 reflections
a = 10.5955 (6) Åθ = 2.3–28.3°
b = 4.0782 (3) ŵ = 2.25 mm1
c = 13.4127 (8) ÅT = 294 K
β = 98.738 (1)°Parallelepiped, yellow
V = 572.84 (6) Å30.29 × 0.28 × 0.24 mm
Z = 2
Data collection top
Bruker SMART APEX area-detector
diffractometer
1430 independent reflections
Radiation source: normal-focus sealed tube1376 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
ω scansθmax = 28.3°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1414
Tmin = 0.561, Tmax = 0.614k = 55
7211 measured reflectionsl = 1717
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.018All H-atom parameters refined
wR(F2) = 0.043 w = 1/[σ2(Fo2) + (0.0181P)2 + 0.3434P]
where P = (Fo2 + 2Fc2)/3
S = 1.10(Δ/σ)max < 0.001
1430 reflectionsΔρmax = 0.73 e Å3
86 parametersΔρmin = 0.74 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.072 (2)
Crystal data top
[Cd(CN)2(CH4N2S)2]·H2OV = 572.84 (6) Å3
Mr = 334.70Z = 2
Monoclinic, P2/nMo Kα radiation
a = 10.5955 (6) ŵ = 2.25 mm1
b = 4.0782 (3) ÅT = 294 K
c = 13.4127 (8) Å0.29 × 0.28 × 0.24 mm
β = 98.738 (1)°
Data collection top
Bruker SMART APEX area-detector
diffractometer
1430 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1376 reflections with I > 2σ(I)
Tmin = 0.561, Tmax = 0.614Rint = 0.017
7211 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0180 restraints
wR(F2) = 0.043All H-atom parameters refined
S = 1.10Δρmax = 0.73 e Å3
1430 reflectionsΔρmin = 0.74 e Å3
86 parameters
Special details top

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
xyzUiso*/Ueq
Cd10.25000.06581 (5)0.25000.03756 (9)
S10.35766 (4)0.31297 (11)0.39821 (3)0.03220 (11)
C10.06927 (16)0.2357 (5)0.29604 (12)0.0340 (3)
C20.28176 (16)0.2070 (4)0.49904 (12)0.0322 (3)
N10.02293 (17)0.3264 (6)0.31974 (14)0.0499 (4)
N20.16014 (18)0.2695 (6)0.49815 (14)0.0535 (5)
N30.3466 (2)0.0687 (6)0.57851 (14)0.0518 (5)
O10.75000.2524 (6)0.25000.0451 (5)
H10.811 (3)0.376 (7)0.267 (2)0.059 (8)*
H20.121 (3)0.355 (8)0.451 (2)0.068 (9)*
H30.127 (3)0.243 (7)0.551 (2)0.056 (7)*
H40.429 (4)0.021 (8)0.578 (3)0.078 (10)*
H50.313 (3)0.013 (7)0.619 (3)0.064 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.02792 (11)0.05064 (14)0.03652 (12)0.0000.01265 (7)0.000
S10.0315 (2)0.0395 (2)0.02651 (18)0.00063 (16)0.00713 (14)0.00102 (16)
C10.0321 (8)0.0416 (9)0.0291 (7)0.0028 (7)0.0072 (6)0.0029 (7)
C20.0352 (8)0.0371 (8)0.0249 (7)0.0004 (7)0.0063 (6)0.0031 (6)
N10.0367 (8)0.0677 (12)0.0477 (9)0.0040 (8)0.0145 (7)0.0077 (9)
N20.0403 (9)0.0892 (16)0.0338 (8)0.0155 (10)0.0148 (7)0.0124 (9)
N30.0417 (9)0.0832 (15)0.0319 (8)0.0100 (9)0.0099 (7)0.0164 (9)
O10.0373 (10)0.0563 (13)0.0423 (10)0.0000.0076 (8)0.000
Geometric parameters (Å, º) top
Cd1—C1i2.2108 (17)C2—N21.312 (2)
Cd1—C12.2108 (17)N2—H20.78 (3)
Cd1—S12.6363 (5)N2—H30.84 (3)
Cd1—S1i2.6363 (5)N3—H40.90 (4)
S1—C21.7300 (17)N3—H50.72 (4)
C1—N11.134 (2)O1—H10.83 (3)
C2—N31.305 (2)
C1i—Cd1—C1143.47 (10)N3—C2—S1119.80 (15)
C1i—Cd1—S195.76 (4)N2—C2—S1121.13 (14)
C1—Cd1—S1105.48 (5)C2—N2—H2120 (2)
C1i—Cd1—S1i105.48 (5)C2—N2—H3120.4 (19)
C1—Cd1—S1i95.76 (4)H2—N2—H3119 (3)
S1—Cd1—S1i108.26 (2)C2—N3—H4119 (2)
C2—S1—Cd1104.11 (6)C2—N3—H5119 (3)
N1—C1—Cd1179.22 (18)H4—N3—H5122 (3)
N3—C2—N2119.05 (18)
Symmetry code: (i) x+1/2, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H5···O1ii0.72 (4)2.26 (4)2.961 (2)166 (3)
N3—H4···S1ii0.90 (4)2.61 (4)3.470 (2)159 (3)
N2—H3···N1iii0.84 (3)2.22 (3)3.035 (2)163 (3)
N2—H2···N1iv0.78 (3)2.51 (3)3.286 (3)171 (3)
O1—H1···N1v0.83 (3)2.16 (3)2.988 (2)176 (3)
Symmetry codes: (ii) x+1, y, z+1; (iii) x, y, z+1; (iv) x, y+1, z; (v) x+1, y+1, z.

Experimental details

Crystal data
Chemical formula[Cd(CN)2(CH4N2S)2]·H2O
Mr334.70
Crystal system, space groupMonoclinic, P2/n
Temperature (K)294
a, b, c (Å)10.5955 (6), 4.0782 (3), 13.4127 (8)
β (°) 98.738 (1)
V3)572.84 (6)
Z2
Radiation typeMo Kα
µ (mm1)2.25
Crystal size (mm)0.29 × 0.28 × 0.24
Data collection
DiffractometerBruker SMART APEX area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.561, 0.614
No. of measured, independent and
observed [I > 2σ(I)] reflections
7211, 1430, 1376
Rint0.017
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.018, 0.043, 1.10
No. of reflections1430
No. of parameters86
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.73, 0.74

Computer programs: SMART (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H5···O1i0.72 (4)2.26 (4)2.961 (2)166 (3)
N3—H4···S1i0.90 (4)2.61 (4)3.470 (2)159 (3)
N2—H3···N1ii0.84 (3)2.22 (3)3.035 (2)163 (3)
N2—H2···N1iii0.78 (3)2.51 (3)3.286 (3)171 (3)
O1—H1···N1iv0.83 (3)2.16 (3)2.988 (2)176 (3)
Symmetry codes: (i) x+1, y, z+1; (ii) x, y, z+1; (iii) x, y+1, z; (iv) x+1, y+1, z.
 

Acknowledgements

We gratefully acknowledge King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia for providing access to the X-ray facility.

References

First citationAhmad, S., Sadaf, H., Akkurt, M., Sharif, S. & Khan, I. U. (2009). Acta Cryst. E65, m1191–m1192.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationBruker (2008). SMART and SAINT. Bruker AXS Inc., Madison. Wisconsin, USA.  Google Scholar
First citationCorao, E. & Baggio, S. (1969). Inorg. Chim. Acta, 3, 617–622.  CSD CrossRef CAS Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationHanif, M., Ahmad, S., Altaf, M. & Stoeckli-Evans, H. (2007). Acta Cryst. E63, m2594.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationMalik, M. R., Ali, S., Fettouhi, M., Isab, A. A. & Ahmad, S. (2010). J. Struct. Chem. 51, 993–996.  CrossRef Google Scholar
First citationMarcos, C., Alía, J. M., Adovasio, V., Prieto, M. & García-Granda, S. (1998). Acta Cryst. C54, 1225–1229.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationNawaz, S., Sadaf, S., Fettouhi, M., Fazal, A. & Ahmad, S. (2010a). Acta Cryst. E66, m950.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationNawaz, S., Sadaf, S., Fettouhi, M., Fazal, A. & Ahmad, S. (2010b). Acta Cryst. E66, m951.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationRajesh, N. P., Kannan, V., Ashok, M., Sivaji, K., Raghavan, P. S. & Ramasamy, P. (2004). J. Cryst. Growth, 262, 561–566.  Web of Science CrossRef CAS Google Scholar
First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationStoev, M. & Ruseva, S. (1994). Monatsh. Chem. 125, 599–606.  CrossRef CAS Web of Science Google Scholar
First citationWang, X. Q., Yu, W. T., Xu, D., Lu, M. K. & Yuan, D. R. (2002). Acta Cryst. C58, m336–m337.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationYoshikawa, H., Nishikiori, S. & Ishida, T. (2003). J. Phys. Chem. B, 107, 9261–9267.  Web of Science CSD CrossRef CAS Google Scholar

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