Tetra­aqua­(2,2′-bipyridine-κ2N,N′)magnesium(II) bis­(4-fluoro­benzoate)

Zhang, B.-S.; Qiu, J.-P.; Liu, L.-H.; Xu, W.

doi:10.1107/S1600536810047690

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 12| December 2010| Page m1624

https://doi.org/10.1107/S1600536810047690

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Tetraaqua(2,2′-bipyridine-κ²N,N′)magnesium(II) bis(4-fluorobenzoate)

Bi-Song Zhang,^a ^* Jian-Ping Qiu,^a Li-Hua Liu ^a and Wei Xu ^b

^aCollege of Material Science and Chemical Engineering, Jinhua College of Profession and Technology, Jinhua, Zhejiang 321017, People's Republic of China, and ^bMunicipal Key Laboratory of Inorganic Materials Chemistry, Institute for Solid State Chemistry, Ninbo University, Ningbo 315211, People's Republic of China
^*Correspondence e-mail: zbs_jy@163.com

(Received 4 November 2010; accepted 17 November 2010; online 24 November 2010)

The title compound, [Mg(C₁₀H₈N₂)(H₂O)₄](C₇H₄FO₂)₂, consists of a bivalent [Mg(C₁₀H₈N₂)(H₂O)₄]²⁺ cation and two 4-fluorbenzoate anions. In the complex cation, the Mg^II atom is coordinated by two N atoms from a 2,2′-bipyridine ligand and four water O atoms in a distorted MgN₂O₄ octahedral geometry. The Mg^II atom is located on a twofold rotation axis and thus a cation exhibits C₂ molecular symmetry. The 2,2′-bipyridine ligands exhibit nearly perfect planarity (r.m.s. deviations = 0.0061 Å). In the crystal, O—H⋯O and C—H⋯O hydrogen bonds link the cations and anions into a three-dimensional supramolecular network.

Related literature

For related magnesium(II) complexes with 1,10-phenanthroline and pyridine ligands, see: Halut-Desportes (1981 ); Hao et al. (2008 ); Zhang (2004 ); Zhang et al. (2010 ).

Experimental

Crystal data

[Mg(C₁₀H₈N₂)(H₂O)₄](C₇H₄FO₂)₂
M_r = 530.76
Orthorhombic, P b c n
a = 27.911 (6) Å
b = 12.423 (3) Å
c = 7.5895 (15) Å
V = 2631.6 (10) Å³
Z = 4
Mo Kα radiation
μ = 0.13 mm⁻¹
T = 290 K
0.18 × 0.13 × 0.10 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) T_min = 0.979, T_max = 0.987
2316 measured reflections
2310 independent reflections
1741 reflections with I > 2σ(I)
R_int = 0.096

Refinement

R[F² > 2σ(F²)] = 0.070
wR(F²) = 0.207
S = 1.14
2310 reflections
156 parameters
H-atom parameters constrained
Δρ_max = 0.39 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯O4ⁱ	0.82	1.90	2.715 (4)	172
O1—H1B⋯O4ⁱⁱ	0.82	1.90	2.682 (4)	159
O2—H2A⋯O3ⁱⁱⁱ	0.82	1.84	2.661 (3)	173
O2—H2B⋯O4ⁱⁱ	0.82	1.99	2.796 (5)	167
C3—H3⋯O3^iv	0.93	2.55	3.257 (6)	133
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (ii) $[-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]$ ; (iv) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810047690/kp2287sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810047690/kp2287Isup2.hkl

checkCIF report

Comment top

Magnesium(II) ions with 1.10-phenanthroline(phen) and pyridine(bipy) ligands can form tetraaqua(L)_nMagnesium(II)(L = phen, n = 1; L = bipy, n = 2 ) complex cation ( Halut-Desportes, 1981, Hao, et al., 2008, Zhang, 2004, Zhang, et al.,2010.) In this paper we report synthesis and structure of the title compound. The crystal structure of title compound consists of [Mg(H₂O)₄(2,2'-bpy)] ²⁺ complex cations and 4-fluorbenzoate anion (Fig. 1). the cation placed in special position on twofold axis which passes through Mg^II atom and middle C5—C5ⁱ bond of 2,2'-bipy molecule; Symmetry code:(i)-x,y,-z+1/2. In the cation, the Mg^II atom is coordinated by two N atoms from one 2,2'-bipy ligands, four O atoms from four different water molecules, completing a distorted MgN₂O₄ octahedral geometry. The Mg—N bond length is 2.183 (3) Å and Mg—O bond lengths are 2.040 (2) and 2.061 (2)Å. The chelating bipy ligands exhibit nearly perfect planarity (r.m.s. deviations = 0.0061 Å). The mean interplanar distances of 3.8352 (3) Å between adjacent bipy ligands indicate π–π stacking interactions (very weak). The complex cations and 4-fluorbenzoate anins are connected via O—H···O and C—H···O hydrogen bonds (Table 1, Fig. 2) into a three-dimensional supramolecular network.

Related literature top

For related magnesium(II) complexes with 1,10-phenanthrolineand pyridine ligands, see: Halut-Desportes (1981); Hao, et al. (2008); Zhang (2004); Zhang et al. (2010).

Experimental top

[Mg(OH)₂.4MgCO₃.4H₂O} (0.4900 g, 1.00 mmol), 4-fluorbenzoate acid (0.0602 g, 0.43 mmol),2,2'-bipyridine (bipy) (0.0503 g, 0.32 mmol ), CH₃OH/H₂O (v/v = 1:2, 15 mL) were mixed and stirred for 2.0 h. Subsequently, the resulting cream suspension was heated in a 23 mL Teflon-lined stainless steel autoclave at 453 K for 5800 minutes. After the autoclave was cooled to room temperature according to the procedure for 2600 minutes, the solid was filtered off. The resulting filtrate was allowed to stand at room temperature, and slow evaporation for 2 months afforded colourless block single crystals.

Structure description top

For related magnesium(II) complexes with 1,10-phenanthrolineand pyridine ligands, see: Halut-Desportes (1981); Hao, et al. (2008); Zhang (2004); Zhang et al. (2010).

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecule structure of the title compound showing the atom-labelling scheme. The octahedral [Mg(C₁₀H₈N₂)(H₂O)₄]²⁺ complex cation is balanced by two fluorbenzoate anions. The two coordinated water molecules of the complex cation are hydrogen bonded to two anions. Displacement ellipsoids are drawn at the 40% probability level (symmetry code:(i)-x,y,-z+1/2).
	Fig. 2. A packing diagram of the title complex, viewed down the c axis, The O—H···O and C—H···O hydrogen bonds(dashed lines) in the title compound.

Tetraaqua(2,2'-bipyridine-κ²N,N')magnesium(II) bis(4-fluorobenzoate) top

Crystal data top

[Mg(C₁₀H₈N₂)(H₂O)₄](C₇H₄FO₂)₂	F(000) = 1104
M_r = 530.76	D_x = 1.340 Mg m⁻³
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -p 2n 2ab	Cell parameters from 665 reflections
a = 27.911 (6) Å	θ = 3.2–25.0°
b = 12.423 (3) Å	µ = 0.13 mm⁻¹
c = 7.5895 (15) Å	T = 290 K
V = 2631.6 (10) Å³	Block, colourless
Z = 4	0.18 × 0.13 × 0.10 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	2310 independent reflections
Radiation source: fine-focus sealed tube	1741 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.096
ω scans	θ_max = 25.0°, θ_min = 3.2°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −33→33
T_min = 0.979, T_max = 0.987	k = −14→14
2316 measured reflections	l = −8→9

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)] = 0.070	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.207	H-atom parameters constrained
S = 1.14	w = 1/[σ²(F_o²) + (0.0879P)² + 2.3043P] where P = (F_o² + 2F_c²)/3
2310 reflections	(Δ/σ)_max < 0.001
156 parameters	Δρ_max = 0.39 e Å⁻³
0 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

[Mg(C₁₀H₈N₂)(H₂O)₄](C₇H₄FO₂)₂	V = 2631.6 (10) Å³
M_r = 530.76	Z = 4
Orthorhombic, Pbcn	Mo Kα radiation
a = 27.911 (6) Å	µ = 0.13 mm⁻¹
b = 12.423 (3) Å	T = 290 K
c = 7.5895 (15) Å	0.18 × 0.13 × 0.10 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	2310 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	1741 reflections with I > 2σ(I)
T_min = 0.979, T_max = 0.987	R_int = 0.096
2316 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.070	0 restraints
wR(F²) = 0.207	H-atom parameters constrained
S = 1.14	Δρ_max = 0.39 e Å⁻³
2310 reflections	Δρ_min = −0.32 e Å⁻³
156 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
Mg1	0.0000	0.29487 (11)	0.2500	0.0347 (4)
O1	0.05496 (9)	0.4005 (2)	0.2115 (3)	0.0536 (7)
H1A	0.0576	0.4581	0.2632	0.080*
H1B	0.0657	0.4124	0.1128	0.080*
O2	−0.01046 (8)	0.2966 (2)	−0.0187 (3)	0.0509 (7)
H2A	−0.0378	0.2905	−0.0568	0.076*
H2B	0.0122	0.3254	−0.0688	0.076*
O3	0.40257 (9)	0.2093 (2)	0.1617 (4)	0.0680 (9)
O4	0.42874 (8)	0.0949 (2)	0.3633 (3)	0.0482 (7)
N1	0.04711 (9)	0.1555 (2)	0.2250 (4)	0.0418 (7)
F1	0.20665 (10)	0.0891 (3)	0.5077 (5)	0.1243 (14)
C1	0.09402 (13)	0.1603 (3)	0.1902 (5)	0.0544 (10)
H1	0.1090	0.2271	0.1896	0.065*
C2	0.12112 (15)	0.0689 (4)	0.1551 (6)	0.0682 (12)
H2	0.1537	0.0746	0.1312	0.082*
C3	0.09930 (15)	−0.0285 (4)	0.1561 (6)	0.0689 (12)
H3	0.1167	−0.0906	0.1313	0.083*
C4	0.05129 (15)	−0.0346 (3)	0.1944 (6)	0.0586 (10)
H4	0.0360	−0.1011	0.1969	0.070*
C5	0.02579 (12)	0.0585 (3)	0.2293 (4)	0.0415 (8)
C6	0.39599 (12)	0.1476 (3)	0.2874 (5)	0.0426 (8)
C7	0.34578 (6)	0.1330 (2)	0.3515 (3)	0.0454 (8)
C8	0.31097 (9)	0.20812 (19)	0.3063 (4)	0.0666 (12)
H8	0.3192	0.2683	0.2400	0.080*
C9	0.26384 (8)	0.1933 (2)	0.3604 (5)	0.0860 (16)
H9	0.2405	0.2436	0.3302	0.103*
C10	0.25153 (7)	0.1034 (3)	0.4595 (4)	0.0789 (14)
C11	0.28634 (10)	0.0283 (2)	0.5047 (4)	0.0844 (17)
H11	0.2781	−0.0319	0.5710	0.101*
C12	0.33346 (9)	0.0431 (2)	0.4506 (4)	0.0663 (12)
H12	0.3568	−0.0072	0.4808	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mg1	0.0374 (8)	0.0321 (8)	0.0346 (8)	0.000	−0.0008 (6)	0.000
O1	0.0681 (16)	0.0475 (14)	0.0450 (13)	−0.0212 (12)	0.0090 (12)	−0.0062 (12)
O2	0.0452 (14)	0.0697 (17)	0.0379 (13)	−0.0083 (12)	−0.0036 (10)	0.0040 (12)
O3	0.0505 (16)	0.076 (2)	0.0771 (19)	0.0115 (13)	0.0175 (14)	0.0332 (16)
O4	0.0473 (14)	0.0502 (15)	0.0472 (13)	0.0034 (11)	−0.0090 (11)	−0.0031 (11)
N1	0.0400 (16)	0.0406 (16)	0.0448 (15)	0.0030 (12)	−0.0008 (12)	−0.0011 (13)
F1	0.0611 (18)	0.169 (4)	0.143 (3)	−0.0280 (19)	0.0441 (18)	−0.016 (3)
C1	0.043 (2)	0.049 (2)	0.071 (3)	0.0030 (16)	0.0017 (18)	−0.0011 (19)
C2	0.047 (2)	0.072 (3)	0.085 (3)	0.015 (2)	0.010 (2)	−0.003 (2)
C3	0.066 (3)	0.052 (3)	0.089 (3)	0.024 (2)	0.006 (2)	−0.008 (2)
C4	0.070 (3)	0.036 (2)	0.070 (2)	0.0086 (18)	0.001 (2)	−0.0039 (18)
C5	0.0502 (19)	0.0371 (18)	0.0372 (17)	0.0012 (15)	−0.0021 (15)	−0.0001 (14)
C6	0.0430 (19)	0.0397 (19)	0.0451 (19)	0.0027 (15)	0.0018 (15)	−0.0051 (16)
C7	0.0430 (19)	0.050 (2)	0.0434 (18)	−0.0033 (16)	0.0019 (15)	−0.0017 (16)
C8	0.051 (2)	0.057 (2)	0.092 (3)	0.0051 (19)	0.013 (2)	0.007 (2)
C9	0.050 (3)	0.086 (4)	0.122 (4)	0.011 (2)	0.016 (3)	−0.004 (3)
C10	0.054 (3)	0.104 (4)	0.079 (3)	−0.017 (3)	0.023 (2)	−0.010 (3)
C11	0.073 (3)	0.112 (5)	0.068 (3)	−0.035 (3)	0.005 (2)	0.027 (3)
C12	0.059 (2)	0.081 (3)	0.059 (2)	−0.013 (2)	−0.0045 (19)	0.020 (2)

Geometric parameters (Å, º) top

Mg1—O1ⁱ	2.040 (2)	C2—H2	0.9300
Mg1—O1	2.040 (2)	C3—C4	1.373 (6)
Mg1—O2	2.061 (2)	C3—H3	0.9300
Mg1—O2ⁱ	2.061 (2)	C4—C5	1.384 (5)
Mg1—N1ⁱ	2.183 (3)	C4—H4	0.9300
Mg1—N1	2.183 (3)	C5—C5ⁱ	1.473 (7)
O1—H1A	0.8200	C6—C7	1.494 (4)
O1—H1B	0.8200	C7—C8	1.3900
O2—H2A	0.8201	C7—C12	1.3900
O2—H2B	0.8198	C8—C9	1.3900
O3—C6	1.238 (4)	C8—H8	0.9300
O4—C6	1.263 (4)	C9—C10	1.3900
N1—C1	1.337 (4)	C9—H9	0.9300
N1—C5	1.344 (4)	C10—C11	1.3900
F1—C10	1.317 (3)	C11—C12	1.3900
C1—C2	1.390 (6)	C11—H11	0.9300
C1—H1	0.9300	C12—H12	0.9300
C2—C3	1.355 (6)

O1ⁱ—Mg1—O1	99.93 (16)	C2—C3—C4	119.3 (4)
O1ⁱ—Mg1—O2	91.62 (10)	C2—C3—H3	120.4
O1—Mg1—O2	87.60 (10)	C4—C3—H3	120.4
O1ⁱ—Mg1—O2ⁱ	87.60 (10)	C3—C4—C5	119.8 (4)
O1—Mg1—O2ⁱ	91.62 (10)	C3—C4—H4	120.1
O2—Mg1—O2ⁱ	178.78 (17)	C5—C4—H4	120.1
O1ⁱ—Mg1—N1ⁱ	92.57 (11)	N1—C5—C4	121.1 (3)
O1—Mg1—N1ⁱ	167.41 (12)	N1—C5—C5ⁱ	115.97 (18)
O2—Mg1—N1ⁱ	90.53 (10)	C4—C5—C5ⁱ	122.9 (2)
O2ⁱ—Mg1—N1ⁱ	90.44 (11)	O3—C6—O4	124.4 (3)
O1ⁱ—Mg1—N1	167.41 (12)	O3—C6—C7	117.7 (3)
O1—Mg1—N1	92.57 (11)	O4—C6—C7	117.9 (3)
O2—Mg1—N1	90.44 (11)	C8—C7—C12	120.0
O2ⁱ—Mg1—N1	90.53 (10)	C8—C7—C6	119.6 (2)
N1ⁱ—Mg1—N1	74.99 (15)	C12—C7—C6	120.4 (2)
Mg1—O1—H1A	124.2	C7—C8—C9	120.0
Mg1—O1—H1B	121.4	C7—C8—H8	120.0
H1A—O1—H1B	104.3	C9—C8—H8	120.0
Mg1—O2—H2A	118.7	C8—C9—C10	120.0
Mg1—O2—H2B	110.7	C8—C9—H9	120.0
H2A—O2—H2B	126.6	C10—C9—H9	120.0
C1—N1—C5	118.6 (3)	F1—C10—C11	120.4 (3)
C1—N1—Mg1	124.9 (2)	F1—C10—C9	119.6 (3)
C5—N1—Mg1	116.2 (2)	C11—C10—C9	120.0
N1—C1—C2	122.3 (4)	C10—C11—C12	120.0
N1—C1—H1	118.8	C10—C11—H11	120.0
C2—C1—H1	118.8	C12—C11—H11	120.0
C3—C2—C1	118.9 (4)	C11—C12—C7	120.0
C3—C2—H2	120.5	C11—C12—H12	120.0
C1—C2—H2	120.5	C7—C12—H12	120.0

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
O1—H1A···O4ⁱⁱ	0.82	1.90	2.715 (4)	172
O1—H1B···O4ⁱⁱⁱ	0.82	1.90	2.682 (4)	159
O2—H2A···O3^iv	0.82	1.84	2.661 (3)	173
O2—H2B···O4ⁱⁱⁱ	0.82	1.99	2.796 (5)	167
C3—H3···O3^v	0.93	2.55	3.257 (6)	133

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

Experimental details

Crystal data
Chemical formula	[Mg(C₁₀H₈N₂)(H₂O)₄](C₇H₄FO₂)₂
M_r	530.76
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	290
a, b, c (Å)	27.911 (6), 12.423 (3), 7.5895 (15)
V (Å³)	2631.6 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.13
Crystal size (mm)	0.18 × 0.13 × 0.10

Data collection
Diffractometer	Rigaku R-AXIS RAPID
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.979, 0.987
No. of measured, independent and observed [I > 2σ(I)] reflections	2316, 2310, 1741
R_int	0.096
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.070, 0.207, 1.14
No. of reflections	2310
No. of parameters	156
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.39, −0.32

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O4ⁱ	0.82	1.90	2.715 (4)	172
O1—H1B···O4ⁱⁱ	0.82	1.90	2.682 (4)	159
O2—H2A···O3ⁱⁱⁱ	0.82	1.84	2.661 (3)	173
O2—H2B···O4ⁱⁱ	0.82	1.99	2.796 (5)	167
C3—H3···O3^iv	0.93	2.55	3.257 (6)	133

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

Acknowledgements

The authors gratefully acknowledge financial support by the Education Office of Zhejiang Province (grant No. 20051316) and the Scientific Research Fund of Ningbo University (grant No. XKL09078).

References

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