Bis[2-(1H-benzimidazol-2-yl)acetato-κ2N3,O]bis­(ethanol-κO)nickel(II)

Wang, J.; Nie, J.-H.

doi:10.1107/S160053681204514X

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 12| December 2012| Page m1461

doi:10.1107/S160053681204514X

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Bis[2-(1H-benzimidazol-2-yl)acetato-κ²N³,O]bis(ethanol-κO)nickel(II)

Jun Wang ^a and Jian-Hua Nie ^a ^*

^aZhongshan Polytechnic, Zhongshan, Guangdong 528404, People's Republic of China
^*Correspondence e-mail: Niejianhua.crystal@yahoo.com

(Received 26 October 2012; accepted 31 October 2012; online 7 November 2012)

In the title compound, [Ni(C₉H₇N₂O₂)₂(C₂H₅OH)₂], the Ni^II ion is situated on an inversion center and is coordinated by two N and two O atoms from two 2-(1H-benzimidazol-2-yl)acetate (L) ligands and by two O atoms from two ethanol ligands in a distorted octahedral geometry. In the L ligand, the acetate group deviates significantly from the benzimidazole plane, the C—C—C—O(coordinating) torsion angle being 34.2 (5)°. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the molecules into a two-dimensional supramolecular network parallel to the bc plane.

Related literature

For related structures, see: Chen et al. (2010 ); Gao et al. (2011 ); Guo et al. (2007 ); Peng et al. (2010 ).

Experimental

Crystal data

[Ni(C₉H₇N₂O₂)₂(C₂H₆O)₂]
M_r = 501.18
Monoclinic, P 2₁ /c
a = 10.441 (5) Å
b = 9.639 (4) Å
c = 11.480 (5) Å
β = 98.956 (6)°
V = 1141.3 (9) Å³
Z = 2
Mo Kα radiation
μ = 0.90 mm⁻¹
T = 298 K
0.28 × 0.26 × 0.23 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.788, T_max = 0.821
6022 measured reflections
2231 independent reflections
1411 reflections with I > 2σ(I)
R_int = 0.061

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.107
S = 1.04
2231 reflections
152 parameters
H-atom parameters constrained
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.45 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O2ⁱ	0.85	1.96	2.672 (3)	141
N2—H2A⋯O2ⁱⁱ	0.86	1.93	2.788 (4)	173
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (ii) $[-x+1, y+{\script{1\over 2}}, -z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681204514X/cv5355sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681204514X/cv5355Isup2.hkl

checkCIF report

Comment top

Multidentate ligands containing N donors and carboxylic groups are often employed to construct new metal coordination polymers with different structures (Chen et al., 2010; Gao et al., 2011; Guo et al., 2007; Peng et al., 2010). The main reason is that they have various coordination modes and can form high-dimensional polymers through hydrogen-bonding interactions in the process of self-assembly. In this work, we chose 2-(1H-benzimidazol-2-yl)acetic acid (HL), which contains two N atoms of an imidazole group and one carboxylate group, as the building block to prepare new metal coordination polymers. To date, only three mononuclear complexes based on the HL ligand have been reported (Chen et al.,2010). In this paper, we report the synthesis and structure of the title compound, (I), obtained by the solvothermal reaction of NiCl₂ and HL ligand.

In (I) (Fig. 1), the Ni(II) ion is coordinated by two N and two O atoms from two bidentate chelating L ligands and two O atoms from two ethanol molecules in a distorted octahedral geometry. The Ni—N bond length is equal to 2.055 (3) Å, and the Ni—O distances vary from 2.037 (3) to 2.107 (2) Å. In the crystal, intermolecular O—H···O and N–H···O hydrogen bonds (Table1) involving the carboxylate O atoms, the imidazole N atoms and the coordinated ethanol O atoms link the molecules into a two-dimensional supramolecular network parallel to the bc plane (Fig. 2).

Related literature top

For related structures, see: Chen et al. (2010); Gao et al. (2011); Guo et al. (2007); Peng et al. (2010).

Experimental top

A mixture of NiCl₂ (0.40 mmol), HL (0.40 mmol) and 8 ml C₂H₅OH was sealed into a 15 ml Teflon-lined stainless steel autoclave and then heated at 373 K for 72 h under autogenous pressure. After cooling to room temperature at a rate of 2 K /h, green block crystals of the title compound suitable for X-ray diffraction were obtained (yield: 35%).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at the 30% probability level [symmetry code\: (i) 1 - x, -y, -z].
	Fig. 2. A portion of the crystal packing, showing the two-dimensional supramolecular network. Hydrogen bonds are shown as dashed lines.

Bis[2-(1H-benzimidazol-2-yl)acetato- κ²N³,O]bis(ethanol-κO)nickel(II) top

Crystal data top

[Ni(C₉H₇N₂O₂)₂(C₂H₆O)₂]	F(000) = 524
M_r = 501.18	D_x = 1.458 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1078 reflections
a = 10.441 (5) Å	θ = 2.8–21.1°
b = 9.639 (4) Å	µ = 0.90 mm⁻¹
c = 11.480 (5) Å	T = 298 K
β = 98.956 (6)°	Block, green
V = 1141.3 (9) Å³	0.28 × 0.26 × 0.23 mm
Z = 2

Data collection top

Bruker APEXII CCD area-detector diffractometer	2231 independent reflections
Radiation source: fine-focus sealed tube	1411 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.061
phi and ω scans	θ_max = 26.0°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −8→12
T_min = 0.788, T_max = 0.821	k = −11→11
6022 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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.107	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0364P)²] where P = (F_o² + 2F_c²)/3
2231 reflections	(Δ/σ)_max < 0.001
152 parameters	Δρ_max = 0.36 e Å⁻³
0 restraints	Δρ_min = −0.45 e Å⁻³

Crystal data top

[Ni(C₉H₇N₂O₂)₂(C₂H₆O)₂]	V = 1141.3 (9) Å³
M_r = 501.18	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.441 (5) Å	µ = 0.90 mm⁻¹
b = 9.639 (4) Å	T = 298 K
c = 11.480 (5) Å	0.28 × 0.26 × 0.23 mm
β = 98.956 (6)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	2231 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	1411 reflections with I > 2σ(I)
T_min = 0.788, T_max = 0.821	R_int = 0.061
6022 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.107	H-atom parameters constrained
S = 1.04	Δρ_max = 0.36 e Å⁻³
2231 reflections	Δρ_min = −0.45 e Å⁻³
152 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

	x	y	z	U_iso*/U_eq
Ni1	0.5000	0.0000	0.0000	0.0295 (2)
C7	0.5632 (4)	0.2871 (4)	−0.0656 (3)	0.0303 (9)
C1	0.7327 (4)	0.3710 (4)	0.0516 (3)	0.0372 (10)
C6	0.7025 (4)	0.2385 (4)	0.0887 (3)	0.0310 (9)
C8	0.4525 (4)	0.2834 (4)	−0.1641 (3)	0.0357 (10)
H8A	0.4655	0.3559	−0.2197	0.043*
H8B	0.3741	0.3059	−0.1325	0.043*
C5	0.7763 (4)	0.1803 (4)	0.1874 (4)	0.0451 (11)
H5	0.7568	0.0929	0.2141	0.054*
C4	0.8787 (4)	0.2548 (5)	0.2444 (4)	0.0564 (13)
H4	0.9294	0.2178	0.3109	0.068*
C2	0.8367 (4)	0.4466 (4)	0.1082 (4)	0.0538 (12)
H2	0.8568	0.5341	0.0821	0.065*
C3	0.9081 (4)	0.3863 (4)	0.2039 (4)	0.0574 (13)
H3	0.9789	0.4340	0.2440	0.069*
C9	0.4305 (4)	0.1481 (4)	−0.2311 (3)	0.0302 (9)
O2	0.3884 (3)	0.1537 (2)	−0.3388 (2)	0.0435 (7)
O1	0.4545 (2)	0.0357 (2)	−0.1765 (2)	0.0357 (7)
N1	0.5959 (3)	0.1869 (3)	0.0125 (3)	0.0300 (8)
N2	0.6410 (3)	0.3986 (3)	−0.0456 (3)	0.0382 (8)
H2A	0.6347	0.4739	−0.0864	0.046*
O3	0.3382 (2)	0.1147 (2)	0.0343 (2)	0.0367 (7)
H3A	0.3398	0.2025	0.0416	0.044*
C10	0.2225 (5)	0.0637 (5)	0.0670 (5)	0.0627 (14)
H10A	0.2386	0.0401	0.1502	0.075*
H10B	0.1984	−0.0209	0.0233	0.075*
C11	0.1146 (5)	0.1594 (6)	0.0467 (6)	0.112 (2)
H11A	0.1364	0.2427	0.0913	0.168*
H11B	0.0397	0.1175	0.0710	0.168*
H11C	0.0962	0.1817	−0.0358	0.168*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0404 (5)	0.0212 (4)	0.0268 (4)	−0.0017 (3)	0.0044 (3)	0.0004 (3)
C7	0.039 (3)	0.022 (2)	0.031 (2)	−0.0052 (18)	0.0072 (18)	−0.0016 (17)
C1	0.045 (3)	0.029 (2)	0.037 (2)	−0.002 (2)	0.003 (2)	−0.0036 (18)
C6	0.035 (3)	0.027 (2)	0.031 (2)	−0.0018 (18)	0.0041 (19)	−0.0012 (17)
C8	0.050 (3)	0.024 (2)	0.031 (2)	0.0009 (19)	0.000 (2)	0.0009 (17)
C5	0.052 (3)	0.037 (2)	0.044 (3)	−0.003 (2)	−0.002 (2)	−0.002 (2)
C4	0.057 (4)	0.054 (3)	0.051 (3)	−0.001 (3)	−0.013 (2)	0.000 (2)
C2	0.059 (3)	0.038 (3)	0.060 (3)	−0.015 (2)	−0.002 (3)	0.004 (2)
C3	0.053 (3)	0.049 (3)	0.065 (3)	−0.014 (3)	−0.007 (3)	−0.015 (3)
C9	0.032 (2)	0.027 (2)	0.032 (2)	−0.0036 (18)	0.0043 (18)	−0.0002 (18)
O2	0.071 (2)	0.0274 (15)	0.0280 (16)	−0.0006 (14)	−0.0061 (14)	0.0026 (12)
O1	0.0565 (19)	0.0214 (14)	0.0283 (15)	0.0004 (12)	0.0041 (12)	0.0010 (11)
N1	0.038 (2)	0.0250 (17)	0.0270 (18)	−0.0005 (15)	0.0042 (15)	0.0012 (14)
N2	0.051 (2)	0.0258 (18)	0.037 (2)	−0.0079 (16)	0.0018 (17)	0.0063 (15)
O3	0.0414 (18)	0.0256 (14)	0.0448 (17)	−0.0020 (13)	0.0118 (13)	−0.0006 (12)
C10	0.058 (4)	0.051 (3)	0.083 (4)	−0.007 (3)	0.025 (3)	−0.014 (3)
C11	0.054 (4)	0.089 (5)	0.195 (8)	0.013 (4)	0.025 (4)	0.012 (5)

Geometric parameters (Å, º) top

Ni1—O1ⁱ	2.037 (3)	C5—H5	0.9300
Ni1—O1	2.037 (3)	C4—C3	1.400 (6)
Ni1—N1ⁱ	2.055 (3)	C4—H4	0.9300
Ni1—N1	2.055 (3)	C2—C3	1.358 (6)
Ni1—O3ⁱ	2.107 (2)	C2—H2	0.9300
Ni1—O3	2.107 (2)	C3—H3	0.9300
C7—N1	1.325 (4)	C9—O2	1.247 (4)
C7—N2	1.346 (4)	C9—O1	1.257 (4)
C7—C8	1.487 (5)	N2—H2A	0.8600
C1—N2	1.379 (5)	O3—C10	1.409 (5)
C1—C2	1.384 (5)	O3—H3A	0.8500
C1—C6	1.398 (5)	C10—C11	1.447 (6)
C6—C5	1.386 (5)	C10—H10A	0.9700
C6—N1	1.395 (5)	C10—H10B	0.9700
C8—C9	1.514 (5)	C11—H11A	0.9600
C8—H8A	0.9700	C11—H11B	0.9600
C8—H8B	0.9700	C11—H11C	0.9600
C5—C4	1.367 (5)

O1ⁱ—Ni1—O1	180.0	C5—C4—H4	119.6
O1ⁱ—Ni1—N1ⁱ	87.54 (10)	C3—C4—H4	119.6
O1—Ni1—N1ⁱ	92.46 (10)	C3—C2—C1	116.5 (4)
O1ⁱ—Ni1—N1	92.46 (10)	C3—C2—H2	121.7
O1—Ni1—N1	87.54 (10)	C1—C2—H2	121.7
N1ⁱ—Ni1—N1	180.0	C2—C3—C4	122.3 (4)
O1ⁱ—Ni1—O3ⁱ	91.58 (10)	C2—C3—H3	118.8
O1—Ni1—O3ⁱ	88.42 (10)	C4—C3—H3	118.8
N1ⁱ—Ni1—O3ⁱ	85.58 (11)	O2—C9—O1	123.0 (3)
N1—Ni1—O3ⁱ	94.42 (11)	O2—C9—C8	117.9 (3)
O1ⁱ—Ni1—O3	88.42 (10)	O1—C9—C8	119.1 (3)
O1—Ni1—O3	91.58 (10)	C9—O1—Ni1	129.7 (2)
N1ⁱ—Ni1—O3	94.42 (11)	C7—N1—C6	105.1 (3)
N1—Ni1—O3	85.58 (11)	C7—N1—Ni1	121.3 (2)
O3ⁱ—Ni1—O3	180.0	C6—N1—Ni1	133.5 (2)
N1—C7—N2	112.5 (3)	C7—N2—C1	107.9 (3)
N1—C7—C8	125.8 (3)	C7—N2—H2A	126.0
N2—C7—C8	121.7 (3)	C1—N2—H2A	126.0
N2—C1—C2	132.4 (4)	C10—O3—Ni1	127.8 (2)
N2—C1—C6	105.2 (3)	C10—O3—H3A	109.0
C2—C1—C6	122.4 (4)	Ni1—O3—H3A	122.5
C5—C6—N1	131.0 (3)	O3—C10—C11	114.4 (4)
C5—C6—C1	119.7 (4)	O3—C10—H10A	108.7
N1—C6—C1	109.3 (3)	C11—C10—H10A	108.7
C7—C8—C9	116.4 (3)	O3—C10—H10B	108.7
C7—C8—H8A	108.2	C11—C10—H10B	108.7
C9—C8—H8A	108.2	H10A—C10—H10B	107.6
C7—C8—H8B	108.2	C10—C11—H11A	109.5
C9—C8—H8B	108.2	C10—C11—H11B	109.5
H8A—C8—H8B	107.3	H11A—C11—H11B	109.5
C4—C5—C6	118.2 (4)	C10—C11—H11C	109.5
C4—C5—H5	120.9	H11A—C11—H11C	109.5
C6—C5—H5	120.9	H11B—C11—H11C	109.5
C5—C4—C3	120.8 (4)

N2—C1—C6—C5	−178.9 (3)	N2—C7—N1—Ni1	−177.1 (2)
C2—C1—C6—C5	1.7 (6)	C8—C7—N1—Ni1	4.1 (5)
N2—C1—C6—N1	1.4 (4)	C5—C6—N1—C7	179.3 (4)
C2—C1—C6—N1	−178.0 (4)	C1—C6—N1—C7	−1.1 (4)
N1—C7—C8—C9	−41.6 (5)	C5—C6—N1—Ni1	−3.7 (6)
N2—C7—C8—C9	139.7 (3)	C1—C6—N1—Ni1	175.9 (2)
N1—C6—C5—C4	178.5 (4)	O1ⁱ—Ni1—N1—C7	−154.3 (3)
C1—C6—C5—C4	−1.1 (6)	O1—Ni1—N1—C7	25.7 (3)
C6—C5—C4—C3	−0.1 (7)	O3ⁱ—Ni1—N1—C7	114.0 (3)
N2—C1—C2—C3	179.8 (4)	O3—Ni1—N1—C7	−66.0 (3)
C6—C1—C2—C3	−1.0 (7)	O1ⁱ—Ni1—N1—C6	29.2 (3)
C1—C2—C3—C4	−0.2 (7)	O1—Ni1—N1—C6	−150.8 (3)
C5—C4—C3—C2	0.8 (7)	O3ⁱ—Ni1—N1—C6	−62.6 (3)
C7—C8—C9—O2	−146.1 (4)	O3—Ni1—N1—C6	117.4 (3)
C7—C8—C9—O1	34.2 (5)	N1—C7—N2—C1	0.5 (4)
O2—C9—O1—Ni1	−171.0 (3)	C8—C7—N2—C1	179.4 (3)
C8—C9—O1—Ni1	8.7 (5)	C2—C1—N2—C7	178.1 (4)
N1ⁱ—Ni1—O1—C9	145.8 (3)	C6—C1—N2—C7	−1.2 (4)
N1—Ni1—O1—C9	−34.2 (3)	O1ⁱ—Ni1—O3—C10	−73.1 (3)
O3ⁱ—Ni1—O1—C9	−128.7 (3)	O1—Ni1—O3—C10	106.9 (3)
O3—Ni1—O1—C9	51.3 (3)	N1ⁱ—Ni1—O3—C10	14.3 (3)
N2—C7—N1—C6	0.4 (4)	N1—Ni1—O3—C10	−165.7 (3)
C8—C7—N1—C6	−178.4 (4)	Ni1—O3—C10—C11	−160.5 (4)

Symmetry code: (i) −x+1, −y, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2ⁱⁱ	0.85	1.96	2.672 (3)	141
N2—H2A···O2ⁱⁱⁱ	0.86	1.93	2.788 (4)	173

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

Experimental details

Crystal data
Chemical formula	[Ni(C₉H₇N₂O₂)₂(C₂H₆O)₂]
M_r	501.18
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	10.441 (5), 9.639 (4), 11.480 (5)
β (°)	98.956 (6)
V (Å³)	1141.3 (9)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.90
Crystal size (mm)	0.28 × 0.26 × 0.23

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.788, 0.821
No. of measured, independent and observed [I > 2σ(I)] reflections	6022, 2231, 1411
R_int	0.061
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.107, 1.04
No. of reflections	2231
No. of parameters	152
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.45

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2ⁱ	0.85	1.96	2.672 (3)	140.5
N2—H2A···O2ⁱⁱ	0.86	1.93	2.788 (4)	172.6

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

Acknowledgements

The authors gratefully acknowledge the Science and Technology Research Project of Zhongshan City (grant No. 20114 A256).

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