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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Hexa­aqua­cobalt(II) 3,3′-dicarb­­oxy­bi­phenyl-4,4′-di­carboxyl­ate

aSchool of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221008, People's Republic of China, and bSchool of Chemical Science and Technology, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
*Correspondence e-mail: amudulin@gmail.com

(Received 24 June 2010; accepted 19 July 2010; online 24 July 2010)

In the crystal structure of the title compound, [Co(H2O)6](C16H8O8), both the cation and anion are centrosymmetric. The Co cation displays a CoO6 octa­hedral geometry formed by six water mol­ecules. In the anion, the two carboxyl groups are oriented at dihedral angles of 4.8 (5) and 10.4 (7)° with respect to the benzene ring. Very strong O—H⋯O hydrogen bonds between the protonated and deprotonated carboxylate groups occur. Neighbouring cations and anions are connected through O—H⋯O hydrogen bonds into a three-dimensional supra­molecular structure.

Related literature

For related metal complexes with the biphenyl-3,3′,4,4′-tetra­carboxyl­ate ligand, see: Sun et al. (2009[Sun, L.-X., Qi, Y., Che, Y.-X., Batten, S. R. & Zheng, J.-M. (2009). Cryst. Growth Des. 9, 2995-2998.]); Wang et al. (2005[Wang, X.-L., Cao, Q. & Wang, E.-B. (2005). Eur. J. Inorg. Chem. pp. 3418-3421.], 2006[Wang, X.-L., Cao, Q. & Wang, E.-B. (2006). Cryst. Growth Des. 6, 439-433.]). For the structures containing the 4,4′-dicarb­oxy­biphenyl-3,3′-dicarboxyl­ate ligand, see: Kang et al. (2009a[Kang, J., Huang, C.-C., Jiang, Z.-Q., Huang, S. & Huang, S.-L. (2009a). Acta Cryst. E65, m452.],b[Kang, J., Huang, C.-C., Zhai, L.-S., Qin, X.-H. & Liu, Z.-Q. (2009b). Acta Cryst. E65, m380-m381.]); Zhu et al. (2008[Zhu, S., Zhang, H. & Shao, M. (2008). Transition Met. Chem. 33, 669-680.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(H2O)6](C16H8O8)

  • Mr = 495.25

  • Triclinic, [P \overline 1]

  • a = 6.5197 (14) Å

  • b = 7.9514 (17) Å

  • c = 9.664 (2) Å

  • α = 76.339 (2)°

  • β = 87.656 (2)°

  • γ = 86.221 (2)°

  • V = 485.57 (18) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.96 mm−1

  • T = 293 K

  • 0.23 × 0.19 × 0.12 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.804, Tmax = 0.895

  • 2871 measured reflections

  • 1590 independent reflections

  • 1305 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.169

  • S = 1.00

  • 1590 reflections

  • 146 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.47 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Selected bond lengths (Å)

Co1—O5 2.054 (3)
Co1—O6 2.027 (3)
Co1—O7 2.082 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O4 0.85 (2) 1.55 (2) 2.391 (5) 173 (8)
O5—H5B⋯O4i 0.96 2.17 2.820 (5) 124
O5—H5C⋯O2ii 0.96 1.97 2.789 (4) 142
O6—H6A⋯O3iii 0.96 1.84 2.676 (4) 144
O6—H6C⋯O1ii 0.96 1.79 2.708 (4) 159
O7—H7A⋯O1iv 0.96 1.83 2.749 (5) 159
O7—H7C⋯O3 0.96 1.99 2.822 (5) 144
Symmetry codes: (i) -x+1, -y, -z+1; (ii) x+1, y, z-1; (iii) x+1, y, z; (iv) x, y, z-1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Biphenyl–3,3',4,4'–tetracarboxylic acid have been used to construct high–dimensional supramolecular networks due to their versatile coordination modes and potential covalent or hydrogen bonding interactions with related parts in the assembly process (Sun et al. 2009; Wang et al. 2005) such as one-dimensional covalent zigzag chain coexist with one-dimensional hydrogen-bonded ladder (Wang et al. 2006). Here we reported a mononuclear complex, containing two ionic components of complex [Co(H2O)6](C16H18O8) (I) in which the two parts are connected via O—H···O hydrogen bonds forming a three-dimensional framework. The structure of the compound (I) consists of discrete ionic entities. A labeled diagram of the crystal [Co(H2O)6](C16H18O18) is shown in Fig. 1. In the cations, the metal atom is surrounded by six aqua ligands, exhibiting a slightly distorted octahedral stereochemistry. The cis/trans O—Co—O angles are nearly 90 °. The average Co—O distance for compound (I) is 2.077 Å. The anion 3,3',4,4'–biphenyltetralate contain inversion center. The mean plane was calculated throughout the six atoms of the benzene ring. Because of symmetric reason, the two benzene rings of the biphenyl ligand are coplanar. The carboxylate groups are almost coplanar with the benzene ring with the largest deviation of -0.205 (6) Å for O4. As expected, there are considerable hydrogen bonds in the structure. The bond distances and angles are listed in Table 2. A three–dimensional structure was formed via three kinds of hydrogen bonds between the coordinated water molecules and carboxyl groups which also help to consolide the crystal packing (Fig. 2).

Related literature top

For related metal complexes with the biphenyl-3,3',4,4'-tetracarboxylate ligand, see: Sun et al. (2009); Wang et al. (2005, 2006). For the structures containing the 4,4'-dicarboxybiphenyl-3,3'-dicarboxylate ligand, see: Kang et al. (2009a,b); Zhu et al. (2008).

Experimental top

A mixture of biphenyl-3,3',4,4'-tetracarboxylic acid (0.2 mmol) and Co(NO3)2.6H2O (0.4 mmol) in 12 ml methanol/water (8:3) sealed in a 25 ml Telflon-lined stainless steel autoclave was kept at 393 K for three days. Single crystals suitable for the X-ray experiment were obtained.

Refinement top

The carboxyl H atom was located in a difference map and refined isotropically. The H atoms of aromatic ring and water molecules were generated geometrically and were included in the refinement in the riding model approximation with C—H = 0.93 Å, Uiso(H)= 1.2 Ueq(C) and O—H = 0.96 Å, Uiso(H)= 1.5Ueq(O).

Structure description top

Biphenyl–3,3',4,4'–tetracarboxylic acid have been used to construct high–dimensional supramolecular networks due to their versatile coordination modes and potential covalent or hydrogen bonding interactions with related parts in the assembly process (Sun et al. 2009; Wang et al. 2005) such as one-dimensional covalent zigzag chain coexist with one-dimensional hydrogen-bonded ladder (Wang et al. 2006). Here we reported a mononuclear complex, containing two ionic components of complex [Co(H2O)6](C16H18O8) (I) in which the two parts are connected via O—H···O hydrogen bonds forming a three-dimensional framework. The structure of the compound (I) consists of discrete ionic entities. A labeled diagram of the crystal [Co(H2O)6](C16H18O18) is shown in Fig. 1. In the cations, the metal atom is surrounded by six aqua ligands, exhibiting a slightly distorted octahedral stereochemistry. The cis/trans O—Co—O angles are nearly 90 °. The average Co—O distance for compound (I) is 2.077 Å. The anion 3,3',4,4'–biphenyltetralate contain inversion center. The mean plane was calculated throughout the six atoms of the benzene ring. Because of symmetric reason, the two benzene rings of the biphenyl ligand are coplanar. The carboxylate groups are almost coplanar with the benzene ring with the largest deviation of -0.205 (6) Å for O4. As expected, there are considerable hydrogen bonds in the structure. The bond distances and angles are listed in Table 2. A three–dimensional structure was formed via three kinds of hydrogen bonds between the coordinated water molecules and carboxyl groups which also help to consolide the crystal packing (Fig. 2).

For related metal complexes with the biphenyl-3,3',4,4'-tetracarboxylate ligand, see: Sun et al. (2009); Wang et al. (2005, 2006). For the structures containing the 4,4'-dicarboxybiphenyl-3,3'-dicarboxylate ligand, see: Kang et al. (2009a,b); Zhu et al. (2008).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title complex with the atom-numbering diagram. Ellipsoids were drawn at the 30% probability level.
[Figure 2] Fig. 2. The packing diagram of (I). Hydrogen bonds are marked by dashed line.
Hexaaquacobalt(II) 3,3'-dicarboxybiphenyl-4,4'-dicarboxylate top
Crystal data top
[Co(H2O)6](C16H8O8)Z = 1
Mr = 495.25F(000) = 255
Triclinic, P1Dx = 1.694 Mg m3
a = 6.5197 (14) ÅMo Kα radiation, λ = 0.71073 Å
b = 7.9514 (17) ÅCell parameters from 774 reflections
c = 9.664 (2) Åθ = 2.2–25.0°
α = 76.339 (2)°µ = 0.96 mm1
β = 87.656 (2)°T = 293 K
γ = 86.221 (2)°Block, pink
V = 485.57 (18) Å30.23 × 0.19 × 0.12 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1590 independent reflections
Radiation source: fine-focus sealed tube1305 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
φ and ω scansθmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 77
Tmin = 0.804, Tmax = 0.895k = 99
2871 measured reflectionsl = 1110
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.169H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.1263P)2]
where P = (Fo2 + 2Fc2)/3
1590 reflections(Δ/σ)max < 0.001
146 parametersΔρmax = 0.47 e Å3
1 restraintΔρmin = 0.43 e Å3
Crystal data top
[Co(H2O)6](C16H8O8)γ = 86.221 (2)°
Mr = 495.25V = 485.57 (18) Å3
Triclinic, P1Z = 1
a = 6.5197 (14) ÅMo Kα radiation
b = 7.9514 (17) ŵ = 0.96 mm1
c = 9.664 (2) ÅT = 293 K
α = 76.339 (2)°0.23 × 0.19 × 0.12 mm
β = 87.656 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1590 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
1305 reflections with I > 2σ(I)
Tmin = 0.804, Tmax = 0.895Rint = 0.028
2871 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0481 restraint
wR(F2) = 0.169H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.47 e Å3
1590 reflectionsΔρmin = 0.43 e Å3
146 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
Co11.00000.00000.50000.0281 (3)
O10.5091 (5)0.1808 (4)1.2457 (3)0.0408 (8)
O20.3077 (5)0.1278 (4)1.0880 (4)0.0396 (8)
O30.4682 (5)0.2634 (5)0.6417 (4)0.0494 (10)
O40.2791 (5)0.1755 (4)0.8356 (3)0.0417 (8)
O51.0135 (5)0.0174 (5)0.2911 (3)0.0434 (9)
H5B0.97510.13020.28580.065*
H5C1.15120.00020.25370.065*
O61.2248 (5)0.1707 (5)0.4594 (4)0.0444 (9)
H6A1.30790.15410.54190.067*
H6C1.30890.15080.38030.067*
O70.7843 (5)0.2081 (4)0.4461 (4)0.0441 (9)
H7A0.67630.17600.39460.066*
H7C0.72770.23720.53140.066*
C10.6112 (6)0.2899 (5)1.0027 (4)0.0255 (9)
C20.7719 (6)0.3637 (5)1.0551 (5)0.0257 (9)
H2B0.78230.34631.15320.031*
C30.9157 (6)0.4613 (5)0.9679 (5)0.0267 (9)
C40.8945 (7)0.4888 (6)0.8216 (5)0.0336 (10)
H4B0.98500.55800.75990.040*
C50.7413 (7)0.4147 (6)0.7674 (5)0.0358 (11)
H5A0.73350.43240.66910.043*
C60.5974 (6)0.3144 (5)0.8535 (5)0.0279 (9)
C70.4682 (6)0.1923 (5)1.1202 (5)0.0288 (10)
C80.4405 (7)0.2462 (6)0.7705 (5)0.0311 (10)
H20.293 (12)0.152 (9)0.999 (2)0.10 (3)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0215 (5)0.0511 (6)0.0143 (5)0.0164 (3)0.0002 (3)0.0092 (4)
O10.0359 (17)0.070 (2)0.0193 (19)0.0237 (16)0.0020 (14)0.0103 (15)
O20.0344 (17)0.062 (2)0.025 (2)0.0271 (15)0.0024 (15)0.0103 (16)
O30.046 (2)0.087 (3)0.024 (2)0.0326 (19)0.0002 (16)0.0224 (17)
O40.0316 (17)0.066 (2)0.032 (2)0.0238 (15)0.0005 (14)0.0133 (16)
O50.0368 (18)0.077 (2)0.0222 (18)0.0290 (16)0.0048 (14)0.0167 (16)
O60.0373 (18)0.074 (2)0.028 (2)0.0310 (16)0.0045 (15)0.0191 (16)
O70.0361 (18)0.070 (2)0.0301 (19)0.0101 (16)0.0049 (15)0.0162 (16)
C10.025 (2)0.032 (2)0.022 (2)0.0069 (16)0.0007 (17)0.0092 (17)
C20.026 (2)0.034 (2)0.018 (2)0.0103 (17)0.0028 (17)0.0074 (17)
C30.024 (2)0.033 (2)0.024 (2)0.0054 (17)0.0038 (18)0.0064 (17)
C40.038 (2)0.045 (2)0.022 (2)0.023 (2)0.0027 (19)0.0090 (19)
C50.042 (3)0.045 (3)0.024 (3)0.019 (2)0.002 (2)0.0117 (19)
C60.024 (2)0.034 (2)0.029 (3)0.0078 (17)0.0020 (18)0.0103 (18)
C70.028 (2)0.037 (2)0.026 (3)0.0109 (18)0.0014 (19)0.0126 (18)
C80.029 (2)0.040 (2)0.029 (3)0.0118 (19)0.0047 (19)0.0137 (19)
Geometric parameters (Å, º) top
Co1—O52.054 (3)O7—H7A0.9600
Co1—O5i2.054 (3)O7—H7C0.9600
Co1—O62.027 (3)C1—C21.401 (6)
Co1—O6i2.027 (3)C1—C61.415 (6)
Co1—O72.082 (3)C1—C71.534 (6)
Co1—O7i2.082 (3)C2—C31.383 (6)
O1—C71.233 (5)C2—H2B0.9300
O2—C71.276 (5)C3—C41.390 (6)
O2—H20.85 (2)C3—C3ii1.516 (8)
O3—C81.226 (6)C4—C51.374 (6)
O4—C81.295 (5)C4—H4B0.9300
O5—H5B0.9600C5—C61.389 (6)
O5—H5C0.9601C5—H5A0.9300
O6—H6A0.9600C6—C81.526 (6)
O6—H6C0.9600
O6—Co1—O6i180.0C2—C1—C6118.3 (4)
O6—Co1—O590.40 (13)C2—C1—C7113.4 (4)
O6i—Co1—O589.60 (13)C6—C1—C7128.3 (4)
O6—Co1—O5i89.60 (13)C3—C2—C1123.2 (4)
O6i—Co1—O5i90.40 (13)C3—C2—H2B118.4
O5—Co1—O5i180.0C1—C2—H2B118.4
O6—Co1—O788.72 (14)C2—C3—C4117.5 (4)
O6i—Co1—O791.28 (14)C2—C3—C3ii120.3 (5)
O5—Co1—O789.16 (14)C4—C3—C3ii122.2 (5)
O5i—Co1—O790.84 (14)C5—C4—C3120.6 (4)
O6—Co1—O7i91.28 (14)C5—C4—H4B119.7
O6i—Co1—O7i88.72 (14)C3—C4—H4B119.7
O5—Co1—O7i90.83 (14)C4—C5—C6122.6 (4)
O5i—Co1—O7i89.17 (14)C4—C5—H5A118.7
O7—Co1—O7i180.000 (1)C6—C5—H5A118.7
C7—O2—H2111 (5)C5—C6—C1117.8 (4)
Co1—O5—H5B109.3C5—C6—C8113.7 (4)
Co1—O5—H5C109.4C1—C6—C8128.5 (4)
H5B—O5—H5C109.5O1—C7—O2120.9 (4)
Co1—O6—H6A109.3O1—C7—C1118.8 (4)
Co1—O6—H6C109.1O2—C7—C1120.3 (4)
H6A—O6—H6C109.5O3—C8—O4121.2 (4)
Co1—O7—H7A109.1O3—C8—C6118.9 (4)
Co1—O7—H7C109.5O4—C8—C6119.9 (4)
H7A—O7—H7C109.5
C6—C1—C2—C30.9 (6)C2—C1—C6—C8179.1 (4)
C7—C1—C2—C3178.3 (4)C7—C1—C6—C81.9 (7)
C1—C2—C3—C41.4 (6)C2—C1—C7—O12.9 (6)
C1—C2—C3—C3ii179.4 (4)C6—C1—C7—O1178.0 (4)
C2—C3—C4—C52.8 (7)C2—C1—C7—O2175.6 (4)
C3ii—C3—C4—C5179.2 (5)C6—C1—C7—O23.5 (7)
C3—C4—C5—C62.0 (7)C5—C6—C8—O39.6 (6)
C4—C5—C6—C10.3 (7)C1—C6—C8—O3171.2 (4)
C4—C5—C6—C8179.6 (4)C5—C6—C8—O4168.7 (4)
C2—C1—C6—C51.8 (6)C1—C6—C8—O410.4 (7)
C7—C1—C6—C5177.3 (4)
Symmetry codes: (i) x+2, y, z+1; (ii) x+2, y+1, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O40.85 (2)1.55 (2)2.391 (5)173 (8)
O5—H5B···O4iii0.962.172.820 (5)124
O5—H5C···O2iv0.961.972.789 (4)142
O6—H6A···O3v0.961.842.676 (4)144
O6—H6C···O1iv0.961.792.708 (4)159
O7—H7A···O1vi0.961.832.749 (5)159
O7—H7C···O30.961.992.822 (5)144
Symmetry codes: (iii) x+1, y, z+1; (iv) x+1, y, z1; (v) x+1, y, z; (vi) x, y, z1.

Experimental details

Crystal data
Chemical formula[Co(H2O)6](C16H8O8)
Mr495.25
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)6.5197 (14), 7.9514 (17), 9.664 (2)
α, β, γ (°)76.339 (2), 87.656 (2), 86.221 (2)
V3)485.57 (18)
Z1
Radiation typeMo Kα
µ (mm1)0.96
Crystal size (mm)0.23 × 0.19 × 0.12
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.804, 0.895
No. of measured, independent and
observed [I > 2σ(I)] reflections
2871, 1590, 1305
Rint0.028
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.169, 1.00
No. of reflections1590
No. of parameters146
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.47, 0.43

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Co1—O52.054 (3)Co1—O72.082 (3)
Co1—O62.027 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O40.85 (2)1.55 (2)2.391 (5)173 (8)
O5—H5B···O4i0.962.172.820 (5)124
O5—H5C···O2ii0.961.972.789 (4)142
O6—H6A···O3iii0.961.842.676 (4)144
O6—H6C···O1ii0.961.792.708 (4)159
O7—H7A···O1iv0.961.832.749 (5)159
O7—H7C···O30.961.992.822 (5)144
Symmetry codes: (i) x+1, y, z+1; (ii) x+1, y, z1; (iii) x+1, y, z; (iv) x, y, z1.
 

References

First citationBruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationKang, J., Huang, C.-C., Jiang, Z.-Q., Huang, S. & Huang, S.-L. (2009a). Acta Cryst. E65, m452.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationKang, J., Huang, C.-C., Zhai, L.-S., Qin, X.-H. & Liu, Z.-Q. (2009b). Acta Cryst. E65, m380–m381.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSun, L.-X., Qi, Y., Che, Y.-X., Batten, S. R. & Zheng, J.-M. (2009). Cryst. Growth Des. 9, 2995–2998.  Web of Science CSD CrossRef CAS Google Scholar
First citationWang, X.-L., Cao, Q. & Wang, E.-B. (2005). Eur. J. Inorg. Chem. pp. 3418–3421.  Web of Science CSD CrossRef Google Scholar
First citationWang, X.-L., Cao, Q. & Wang, E.-B. (2006). Cryst. Growth Des. 6, 439–433.  Web of Science CSD CrossRef CAS Google Scholar
First citationZhu, S., Zhang, H. & Shao, M. (2008). Transition Met. Chem. 33, 669–680.  Web of Science CSD CrossRef CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds