(2,2′-Bipyridine-κ2N,N′)bis­(4-chloro­benzoato-κO)zinc

Zhang, B.-S.; Zhu, H.-L.; Li, J.; Dai, D.-D.; Peng, Y.-B.

doi:10.1107/S160053681200699X

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 3| March 2012| Pages m321-m322

doi:10.1107/S160053681200699X

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(2,2′-Bipyridine-κ²N,N′)bis(4-chlorobenzoato-κO)zinc

Bi-Song Zhang,^a ^* Hong-Line Zhu,^b Jun Li,^a Dong-Dong Dai ^a and Yi-Bao Peng ^a

^aCollege of Materials Science and Chemical Engineering, Jinhua College of Profession and Technology, Jinhua, Zhejiang 321017, People's Republic of China, and ^bState Key Laboratory Base of Novel Functional Materials and Preparation, Science Center of Applied Solid State Chemistry Research, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
^*Correspondence e-mail: zbs_jy@163.com

(Received 10 February 2012; accepted 16 February 2012; online 24 February 2012)

In the title compound, [Zn(C₇H₄ClO₂)₂(C₁₀H₈N₂)], the Zn^II atom is coordinated by two O atoms from two 4-chlorobenzoate ligands and two N atoms from a chelating 2,2′-bipyridine (bpy) molecule in a distorted N₂O₂ tetrahedral geometry. The Zn^II atom is located on a twofold rotation axis, which also passes through the mid-point of the central C—C bond of the bpy ligand. In the crystal, weak C—H⋯O hydrogen bonds and π–π stacking interactions between the pyridine rings of the bpy ligands [centroid–centroid distance = 3.642 (3) Å] link the complex molecules into a two-dimensional supramolecular structure parallel to (100). An intramolecular C—H⋯O hydrogen bond is also observed.

Related literature

For zinc(II) complexes with substituted benzoate ligands, see: Aghabozorg et al. (2005 ); Chen et al. (2006 ); Hökelek et al. (2008 ); Lemoine et al. (2004 ); Liu et al. (1998 ); Wei et al. (2002 , 2004 ); Xu et al. (2004 ); Ye & Zhang (2010 ); Zhang et al. (2009 , 2010 ); Zhou et al. (2005 ).

Experimental

Crystal data

[Zn(C₇H₄ClO₂)₂(C₁₀H₈N₂)]
M_r = 532.68
Monoclinic, P 2/c
a = 11.453 (2) Å
b = 8.4896 (17) Å
c = 12.337 (3) Å
β = 107.12 (3)°
V = 1146.4 (5) Å³
Z = 2
Mo Kα radiation
μ = 1.34 mm⁻¹
T = 290 K
0.32 × 0.25 × 0.18 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.675, T_max = 0.787
8641 measured reflections
2012 independent reflections
1560 reflections with I > 2σ(I)
R_int = 0.058

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.121
S = 1.17
2012 reflections
150 parameters
48 restraints
H-atom parameters constrained
Δρ_max = 0.53 e Å⁻³
Δρ_min = −0.36 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1⋯O1ⁱ	0.93	2.55	3.172 (6)	125
C3—H3⋯O2ⁱⁱ	0.93	2.52	3.278 (5)	139
C11—H11⋯O1ⁱⁱⁱ	0.93	2.57	3.330 (5)	139
Symmetry codes: (i) $[-x, y, -z+{\script{1\over 2}}]$ ; (ii) -x, -y+1, -z+1; (iii) $[x, -y+2, z+{\script{1\over 2}}]$ .

Data collection: RAPID-AUTO (Rigaku, 1998 ); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002 ); 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) and DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681200699X/hy2516sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681200699X/hy2516Isup2.hkl

checkCIF report

Comment top

Transition metal complexes with biochemical molecules show interesting physical and/or chemical properties, which may find applications in biological systems. The structure–function–coordination relationships of arylcarboxylates in Zn^II complexes of benzoic acid derivatives may alos be changed depending on the nature and positions of the substituted groups on the benzene ring. Zinc(II) complexes with substituted benzoic acid ligands have been reported (Aghabozorg et al., 2005; Chen et al., 2006; Hökelek et al., 2008; Lemoine et al., 2004; Liu et al., 1998; Wei et al., 2002, 2004; Xu et al., 2004; Ye & Zhang, 2010; Zhang et al., 2009, 2010). In this paper, we report the synthesis and structure of the title complex.

In the title compound, the Zn^II atom is coordinated by two O atoms and two N atoms from two 4-chlorobenzoate ligands and one 2,2'-bipyridine (bpy) molecule in a distorted ZnN₂O₂ tetrahedral geometry. The O1 atom of the 4-chlorobenzoate ligand has a weak interaction with the Zn^II atom [Zn1···O1 = 2.602 (3) Å]. A similar distance has been observed [Zn1···O2 = 2.653 (7)Å] (Zhou et al., 2005). The Zn^II atom is located on a twofold rotation axis, which also passes through the mid-point of the C5—C5ⁱ bond [symmetry code: (i) -x, y, -z+1/2] of the bpy ligand. The bpy ligand exhibits nearly perfect coplanarity (r.m.s. deviation = 0.049 Å). In the crystal, weak C—H···O hydrogen bonds (Table 1) and π–π stacking interactions [centroid–centroid distance = 3.642 (3) Å] between adjacent bpy ligands link the complex molecules into a two-dimensional supramolecular structure parallel to (100).

Related literature top

For zinc(II) complexes with substituted benzoic acid ligands, see: Aghabozorg et al. (2005); Chen et al. (2006); Hökelek et al. (2008); Lemoine et al. (2004); Liu et al. (1998); Wei et al. (2002, 2004); Xu et al. (2004); Ye & Zhang (2010); Zhang et al. (2009, 2010); Zhou et al. (2005).

Experimental top

ZnCl₂ (0.0687 g, 0.504 mmol) was dissolved in appropriate amount of water and then 1M Na₂CO₃ solution was added. ZnCO₃ was obtained by filtration, which was then washed with distilled water for 5 times. The freshly prepared ZnCO₃, 2,2'-bipyridine (0.0388 g, 0.273 mmol) and 4-chlorobenzoic acid (0.0396 g, 0.255 mmol), CH₃OH/H₂O (v/v = 1:2, 15 ml) were mixed and stirred for 2 h. The resulting cream suspension was heated in a 23 ml Teflon-lined stainless steel autoclave at 433 K for 97 h. After the autoclave was cooled to room temperature within 43 h, the solid was filtered off. The resulting filtrate was allowed to stand at room temperature and slow evaporation for 6 weeks afforded colorless block single crystals.

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2002); 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) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry code: (i) -x, y, -z+1/2.]
	Fig. 2. A view of the crystal packing, showing π–π interactions (dashed double arrows), with a centroid–centroid distance of 3.642 (3) Å, and C—H···O hydrogen bonds (dashed lines).

(2,2'-Bipyridine-κ²N,N')bis(4-chlorobenzoato- κO)zinc(II) top

Crystal data top

[Zn(C₇H₄ClO₂)₂(C₁₀H₈N₂)]	F(000) = 540
M_r = 532.68	D_x = 1.543 Mg m⁻³
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 6683 reflections
a = 11.453 (2) Å	θ = 3.0–25.0°
b = 8.4896 (17) Å	µ = 1.34 mm⁻¹
c = 12.337 (3) Å	T = 290 K
β = 107.12 (3)°	Block, colorless
V = 1146.4 (5) Å³	0.32 × 0.25 × 0.18 mm
Z = 2

Data collection top

Rigaku R-AXIS RAPID diffractometer	2012 independent reflections
Radiation source: rotation anode	1560 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.058
ω scans	θ_max = 25.0°, θ_min = 3.0°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −13→13
T_min = 0.675, T_max = 0.787	k = −9→10
8641 measured reflections	l = −14→14

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.121	H-atom parameters constrained
S = 1.17	w = 1/[σ²(F_o²) + (0.051P)² + 0.432P] where P = (F_o² + 2F_c²)/3
2012 reflections	(Δ/σ)_max < 0.001
150 parameters	Δρ_max = 0.53 e Å⁻³
48 restraints	Δρ_min = −0.36 e Å⁻³

Crystal data top

[Zn(C₇H₄ClO₂)₂(C₁₀H₈N₂)]	V = 1146.4 (5) Å³
M_r = 532.68	Z = 2
Monoclinic, P2/c	Mo Kα radiation
a = 11.453 (2) Å	µ = 1.34 mm⁻¹
b = 8.4896 (17) Å	T = 290 K
c = 12.337 (3) Å	0.32 × 0.25 × 0.18 mm
β = 107.12 (3)°

Data collection top

Rigaku R-AXIS RAPID diffractometer	2012 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	1560 reflections with I > 2σ(I)
T_min = 0.675, T_max = 0.787	R_int = 0.058
8641 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	48 restraints
wR(F²) = 0.121	H-atom parameters constrained
S = 1.17	Δρ_max = 0.53 e Å⁻³
2012 reflections	Δρ_min = −0.36 e Å⁻³
150 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Zn1	0.0000	0.78102 (6)	0.2500	0.0564 (2)
Cl2	0.59680 (10)	1.35611 (14)	0.61254 (11)	0.0912 (4)
O1	0.1788 (3)	0.9459 (3)	0.2186 (2)	0.0738 (7)
O2	0.1206 (2)	0.8948 (3)	0.3696 (2)	0.0650 (7)
C1	−0.1402 (4)	0.6021 (6)	0.3867 (4)	0.0889 (13)
H1	−0.1636	0.7013	0.4048	0.107*
C2	−0.1780 (5)	0.4710 (8)	0.4330 (5)	0.122 (2)
H2	−0.2269	0.4814	0.4808	0.146*
C3	−0.1427 (7)	0.3267 (9)	0.4076 (6)	0.144 (3)
H3	−0.1657	0.2369	0.4394	0.172*
C4	−0.0731 (6)	0.3138 (6)	0.3351 (5)	0.121 (2)
H4	−0.0493	0.2150	0.3168	0.145*
C5	−0.0377 (4)	0.4489 (4)	0.2888 (3)	0.0827 (13)
N1	−0.0713 (3)	0.5916 (3)	0.3171 (3)	0.0686 (8)
C6	0.2915 (3)	1.0622 (4)	0.3941 (3)	0.0512 (8)
C7	0.3756 (4)	1.1328 (5)	0.3489 (3)	0.0679 (10)
H7	0.3691	1.1184	0.2726	0.082*
C8	0.4688 (4)	1.2242 (5)	0.4152 (4)	0.0741 (11)
H8	0.5246	1.2720	0.3842	0.089*
C9	0.4779 (3)	1.2436 (4)	0.5275 (4)	0.0629 (10)
C10	0.3952 (4)	1.1763 (5)	0.5739 (3)	0.0690 (10)
H10	0.4017	1.1915	0.6501	0.083*
C11	0.3019 (3)	1.0853 (4)	0.5063 (3)	0.0614 (9)
H11	0.2455	1.0391	0.5375	0.074*
C12	0.1909 (3)	0.9613 (4)	0.3207 (3)	0.0553 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.0659 (4)	0.0427 (3)	0.0618 (4)	0.000	0.0206 (3)	0.000
Cl2	0.0755 (7)	0.0805 (7)	0.1037 (9)	−0.0151 (6)	0.0048 (6)	−0.0030 (6)
O1	0.097 (2)	0.0728 (16)	0.0544 (16)	−0.0092 (15)	0.0258 (14)	−0.0083 (13)
O2	0.0722 (16)	0.0637 (15)	0.0639 (16)	−0.0123 (13)	0.0275 (13)	−0.0042 (12)
C1	0.080 (3)	0.105 (3)	0.081 (3)	−0.019 (2)	0.021 (2)	0.025 (2)
C2	0.104 (4)	0.151 (4)	0.097 (4)	−0.054 (4)	0.009 (3)	0.050 (4)
C3	0.165 (6)	0.116 (4)	0.110 (5)	−0.073 (4)	−0.021 (4)	0.058 (4)
C4	0.161 (5)	0.059 (3)	0.103 (4)	−0.040 (3)	−0.023 (3)	0.024 (3)
C5	0.104 (3)	0.0480 (18)	0.069 (3)	−0.013 (2)	−0.018 (2)	0.0074 (17)
N1	0.073 (2)	0.0545 (17)	0.070 (2)	−0.0075 (15)	0.0080 (16)	0.0108 (14)
C6	0.0590 (19)	0.0428 (16)	0.055 (2)	0.0036 (15)	0.0216 (15)	0.0031 (14)
C7	0.077 (3)	0.072 (2)	0.064 (2)	−0.006 (2)	0.035 (2)	−0.0049 (19)
C8	0.070 (3)	0.075 (3)	0.086 (3)	−0.012 (2)	0.038 (2)	0.002 (2)
C9	0.061 (2)	0.0511 (19)	0.074 (3)	0.0037 (17)	0.0154 (19)	0.0019 (17)
C10	0.079 (3)	0.072 (2)	0.054 (2)	−0.007 (2)	0.0172 (19)	−0.0008 (18)
C11	0.068 (2)	0.064 (2)	0.056 (2)	−0.0094 (18)	0.0234 (17)	0.0027 (17)
C12	0.065 (2)	0.0435 (17)	0.058 (2)	0.0065 (16)	0.0180 (17)	−0.0001 (15)

Geometric parameters (Å, º) top

Zn1—O2	1.954 (2)	C4—H4	0.9300
Zn1—N1	2.082 (3)	C5—N1	1.347 (5)
Zn1—O1	2.602 (3)	C5—C5ⁱ	1.466 (10)
Cl2—C9	1.740 (4)	C6—C11	1.368 (5)
O1—C12	1.233 (4)	C6—C7	1.384 (5)
O2—C12	1.272 (4)	C6—C12	1.506 (5)
C1—N1	1.329 (6)	C7—C8	1.377 (6)
C1—C2	1.377 (6)	C7—H7	0.9300
C1—H1	0.9300	C8—C9	1.368 (6)
C2—C3	1.356 (10)	C8—H8	0.9300
C2—H2	0.9300	C9—C10	1.368 (5)
C3—C4	1.366 (11)	C10—C11	1.382 (5)
C3—H3	0.9300	C10—H10	0.9300
C4—C5	1.394 (6)	C11—H11	0.9300

O2—Zn1—O2ⁱ	120.76 (15)	C2—C3—C4	119.6 (5)
O2—Zn1—N1	110.75 (11)	C2—C3—H3	120.2
O2ⁱ—Zn1—N1	114.15 (11)	C4—C3—H3	120.2
O2—Zn1—N1ⁱ	114.15 (11)	C3—C4—C5	119.9 (6)
O2ⁱ—Zn1—N1ⁱ	110.75 (11)	C3—C4—H4	120.1
N1—Zn1—N1ⁱ	78.9 (2)	C5—C4—H4	120.1
O2—Zn1—C12	28.13 (10)	N1—C5—C4	119.6 (5)
O2ⁱ—Zn1—C12	107.47 (11)	N1—C5—C5ⁱ	115.9 (2)
N1—Zn1—C12	135.29 (12)	C4—C5—C5ⁱ	124.5 (4)
N1ⁱ—Zn1—C12	101.44 (12)	C1—N1—C5	119.8 (4)
O2—Zn1—C12ⁱ	107.47 (11)	C1—N1—Zn1	125.5 (3)
O2ⁱ—Zn1—C12ⁱ	28.13 (10)	C5—N1—Zn1	114.6 (3)
N1—Zn1—C12ⁱ	101.44 (12)	C11—C6—C7	118.8 (3)
N1ⁱ—Zn1—C12ⁱ	135.29 (12)	C11—C6—C12	120.9 (3)
C12—Zn1—C12ⁱ	107.90 (14)	C7—C6—C12	120.3 (3)
O2—Zn1—O1	55.55 (9)	C8—C7—C6	120.9 (4)
O2ⁱ—Zn1—O1	91.94 (10)	C8—C7—H7	119.6
N1—Zn1—O1	153.21 (11)	C6—C7—H7	119.6
N1ⁱ—Zn1—O1	86.47 (11)	C9—C8—C7	119.0 (4)
C12—Zn1—O1	27.42 (9)	C9—C8—H8	120.5
C12ⁱ—Zn1—O1	104.74 (10)	C7—C8—H8	120.5
O2—Zn1—O1ⁱ	91.94 (10)	C10—C9—C8	121.2 (4)
O2ⁱ—Zn1—O1ⁱ	55.55 (9)	C10—C9—Cl2	119.5 (3)
N1—Zn1—O1ⁱ	86.47 (11)	C8—C9—Cl2	119.3 (3)
N1ⁱ—Zn1—O1ⁱ	153.21 (11)	C9—C10—C11	119.3 (4)
C12—Zn1—O1ⁱ	104.74 (10)	C9—C10—H10	120.4
C12ⁱ—Zn1—O1ⁱ	27.42 (9)	C11—C10—H10	120.4
O1—Zn1—O1ⁱ	114.90 (12)	C6—C11—C10	120.8 (4)
C12—O1—Zn1	76.2 (2)	C6—C11—H11	119.6
C12—O2—Zn1	105.5 (2)	C10—C11—H11	119.6
N1—C1—C2	122.1 (5)	O1—C12—O2	122.8 (3)
N1—C1—H1	118.9	O1—C12—C6	120.7 (3)
C2—C1—H1	118.9	O2—C12—C6	116.5 (3)
C3—C2—C1	118.9 (6)	O1—C12—Zn1	76.4 (2)
C3—C2—H2	120.5	O2—C12—Zn1	46.41 (16)
C1—C2—H2	120.5	C6—C12—Zn1	162.9 (3)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···O1ⁱ	0.93	2.55	3.172 (6)	125
C3—H3···O2ⁱⁱ	0.93	2.52	3.278 (5)	139
C11—H11···O1ⁱⁱⁱ	0.93	2.57	3.330 (5)	139

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

Experimental details

Crystal data
Chemical formula	[Zn(C₇H₄ClO₂)₂(C₁₀H₈N₂)]
M_r	532.68
Crystal system, space group	Monoclinic, P2/c
Temperature (K)	290
a, b, c (Å)	11.453 (2), 8.4896 (17), 12.337 (3)
β (°)	107.12 (3)
V (Å³)	1146.4 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.34
Crystal size (mm)	0.32 × 0.25 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPID diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.675, 0.787
No. of measured, independent and observed [I > 2σ(I)] reflections	8641, 2012, 1560
R_int	0.058
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.121, 1.17
No. of reflections	2012
No. of parameters	150
No. of restraints	48
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.53, −0.36

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···O1ⁱ	0.930	2.550	3.172 (6)	125
C3—H3···O2ⁱⁱ	0.930	2.520	3.278 (5)	139
C11—H11···O1ⁱⁱⁱ	0.930	2.570	3.330 (5)	139

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

Acknowledgements

The authors gratefully acknowledge the financial support of the Education Office of Zhejiang Province (grant No. 20051316).

References

Aghabozorg, H., Nakhjavan, B., Zabihi, F., Ramezanipour, F. & Aghabozorg, H. R. (2005). Acta Cryst. E61, m2664–m2666. Web of Science CSD CrossRef IUCr Journals Google Scholar
Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Chen, H., Xu, X.-Y., Gao, J., Yang, X.-J., Lu, L.-D. & Wang, X. (2006). Huaxue Shiji (Chem. React.), 28, 478–480. CAS Google Scholar
Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan. Google Scholar
Hökelek, T., Çaylak, N. & Necefoğlu, H. (2008). Acta Cryst. E64, m458–m459. Web of Science CSD CrossRef IUCr Journals Google Scholar
Lemoine, P., Bendada, K. & Viossat, B. (2004). Acta Cryst. C60, m489–m491. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Liu, C.-M., You, X.-Z. & Chen, W. (1998). J. Coord. Chem. 46, 233–243. Web of Science CrossRef CAS Google Scholar
Rigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan. Google Scholar
Rigaku/MSC (2002). CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wei, Y., Yuan, C. & Yang, P. (2004). Acta Cryst. E60, m1686–m1688. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Wei, D.-Y., Zheng, Y.-Q. & Lin, J.-L. (2002). Z. Anorg. Allg. Chem. 628, 2005–2012. CrossRef CAS Google Scholar
Xu, H., Liang, Y., Su, Z., Zhao, Y., Shao, K., Zhang, H. & Yue, S. (2004). Acta Cryst. E60, m142–m144. Web of Science CSD CrossRef IUCr Journals Google Scholar
Ye, S.-F. & Zhang, B.-S. (2010). Acta Cryst. E66, m474. Web of Science CrossRef IUCr Journals Google Scholar
Zhang, B.-Y., Nie, J.-J. & Xu, D.-J. (2009). Acta Cryst. E65, m880. Web of Science CSD CrossRef IUCr Journals Google Scholar
Zhang, B.-S., Ye, S.-F., Li, Y.-X. & Xu, W. (2010). Acta Cryst. E66, m1357–m1358. Web of Science CSD CrossRef IUCr Journals Google Scholar
Zhou, Y.-F., Lin, W.-J., Huang, Y.-G. & Hong, M.-C. (2005). Acta Cryst. E61, m177–m179. Web of Science CSD CrossRef IUCr Journals Google Scholar