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Bis(2,2′-bi­pyridine-κ2N,N′)(croconato-κ2O,O′)nickel(II)

aState Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, Shandong Province, People's Republic of China
*Correspondence e-mail: fangqi@sdu.edu.cn

(Received 17 September 2008; accepted 16 October 2008; online 25 October 2008)

The title compound, [Ni(C5O5)(C10H8N2)2], lies across a crystallographic twofold axis, around which two 2,2′-bipyridine (2,2′-bipy) ligands are arranged in a propeller manner. The local geometry of the NiN4O2 coordination core basically adopts an octa­hedral geometry. The mol­ecular twofold axis is along the direction of the mol­ecular dipole moment, and the complex is packed with its dipole moment alternately along the +b and −b directions. The crystal structure is stabilized by inter­molecular C—H⋯O hydrogen bonds.

Related literature

For the synthesis, see: Chen et al. (2008[Chen, H.-F., Chen, H.-Y., Chen, X., Batsanov, A. S. & Fang, Q. (2008). Acta Cryst. E64, m172.]). For related structures, see: Chen et al. (2005[Chen, H.-Y., Fang, Q., Xue, G. & Yu, W.-T. (2005). Acta Cryst. C61, m535-m537.], 2007[Chen, X., Chen, H.-F., Xue, G., Chen, H.-Y., Yu, W.-T. & Fang, Q. (2007). Acta Cryst. C63, m166-m168.]). For other related literature, see: Coronado et al. (2007[Coronado, E., Curreli, S., Giménez-Saiz, C., Gómez-García, C.-J., Deplano, P., Mercuri, M.-L., Serpe, A., Pilia, L., Faulmann, C. & Canadell, E. (2007). Inorg. Chem. 46, 4446-4457.]); Wang et al. (2002[Wang, C. C., Yang, C.-H. & Lee, G.-H. (2002). Inorg. Chem. 41, 1015-1018.]).

[Scheme 1]

Experimental

Crystal data
  • [Ni(C5O5)(C10H8N2)2]

  • Mr = 511.13

  • Orthorhombic, P b c n

  • a = 12.725 (5) Å

  • b = 10.752 (5) Å

  • c = 15.733 (5) Å

  • V = 2152.6 (15) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.95 mm−1

  • T = 293 (2) K

  • 0.20 × 0.19 × 0.10 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (APEX2; Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.821, Tmax = 0.902

  • 10055 measured reflections

  • 2466 independent reflections

  • 1536 reflections with I > 2σ(I)

  • Rint = 0.089

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.102

  • S = 1.02

  • 2466 reflections

  • 160 parameters

  • H-atom parameters constrained

  • Δρmax = 0.26 e Å−3

  • Δρmin = −0.38 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C4—H4⋯O1i 0.93 2.57 3.340 (4) 141
C8—H8⋯O2ii 0.93 2.24 3.114 (4) 156
C9—H9⋯O3iii 0.93 2.57 3.222 (4) 127
Symmetry codes: (i) [x, -y+1, z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: APEX2; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

The croconate C5O52- anion has attracted increasing attention in recent years because this polydentate ligand gave rise to a variety of interesting complexes (Chen et al., 2008; Coronado et al., 2007; Chen et al., 2005; Wang et al., 2002;). Typically, the C5O52- anion serves as a terminal bidentate chelate ligand or a bridging ligand utilizing more than two O atoms for coordination. We previously reported a mixing-coordinated complex [Ni(C5O5)(phen)2] with 1,10-phenanthroline (phen) as the first ligand and the C5O52- anion as the second ligand (Chen et al., 2007). The similar chelating behavior of 2,2'-bipy and 1,10-phen prompted us to replace phen ligand by 2,2'-bipy. In this report, the structure of this mixing-coordinated complex is reported.

The title compound crystalizes to the same space group as [Ni(C5O5)(phen)2]. Both crystals have very similar cell parameters and show many common features. The chiral molecule lies across twofold axis which is along the direction of the molecular dipole moment. Around the molecular axis, two 2,2'-bipy ligands are arranged in a propeller manner. The Ni2+ is coordinated by four N atoms of the two 2,2'-bipy ligands and two O atoms of a croconate ligand to furnish a slightly distored octahedral NiN4O2 coordination core. The dihedral angle between the croconate plane and a 2,2'-bipy plane is 88.7 (1)°, and that between the two 2,2'-bipy planes is 81.9 (1)° in [Ni(C5O5) (2,2'-bipy)2]. These are close to the corresponding dihedral angles (86.9 (1)° and 86.6 (1)°) in [Ni(C5O5)(phen)2]. The C—O bond lengths involving coordinated O atoms are longer than those of other C—O bonds. In both crystals, molecules packed alternately along +b and-b directions.

However, we can not fail to notice some differences between the two crystals. The Ni—O band length of [Ni(C5O5)(2,2'-bipy)2] {2.102 (2) Å} is longer than that {2.098 (3) Å} of [Ni(C5O5)(phen)2]. Meanwhile, the Ni—N band lengths of [Ni(C5O5)(2,2'-bipy)2] {2.059 (2), 2.066 (2) Å} is considerably shorter than those {2.071 (3), 2.088 (3) Å} of [Ni(C5O5)(phen)2]. It seems that 2,2'-bipyridine is a stronger ligand to Ni2+ in comparison with 1,10-phenanthroline. The crystal structure is stabilized by intermolecular C—H···O hydrogen bonds (Table 1).

Related literature top

For the synthesis, see: Chen et al. (2008). For related structures, see: Chen et al. (2005, 2007). For other related literature, see: Coronado et al. (2007); Wang et al. (2002).

Experimental top

[K2(C5O5)] (0.050 g, 0.23 mmol) and NiCl2.6H2O (0.060 g, 0.25 mmol) were dissolved in mixed solvent of water (15 ml) and dimethylformamide (10 ml). Then 2,2'-bipy (0.080 g, 0.51 mmol) was added. The mixture was heated to 340–350 K under continuous stirring for 20 min and then filtered. The green-yellow prisms crystals were obtained by slow evaporation at 313 K.

Refinement top

All H atoms were positioned geometrically and allowed to ride on their attached atom. The C—H bond lengths for aromatic groups were set to 0.93 Å.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: APEX2 (Bruker, 2005); 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: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of [Ni(C5O5) (2,2'-bipy)2]. Displacement ellipsoids are drawn at the 30% probability level and H atoms have been omitted. [symmetry code: (i) -x + 1, y, -z + 3/2.]
Bis(2,2'-bipyridine-κ2N,N')(croconato-κ2O,O')nickel(II) top
Crystal data top
[Ni(C5O5)(C10H8N2)2]F(000) = 1048
Mr = 511.13Dx = 1.577 Mg m3
Orthorhombic, PbcnMo Kα radiation, λ = 0.71069 Å
Hall symbol: -P_2n 2abCell parameters from 2518 reflections
a = 12.725 (5) Åθ = 2.5–23.4°
b = 10.752 (5) ŵ = 0.95 mm1
c = 15.733 (5) ÅT = 293 K
V = 2152.6 (15) Å3Prism, green-yellow
Z = 40.20 × 0.19 × 0.10 mm
Data collection top
Bruker APEXII CCD
diffractometer
2466 independent reflections
Radiation source: fine-focus sealed tube1536 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.089
Detector resolution: 10.0 pixels mm-1θmax = 27.5°, θmin = 2.5°
ϕ and ω scansh = 1516
Absorption correction: multi-scan
(APEX2; Bruker, 2005)
k = 1310
Tmin = 0.821, Tmax = 0.902l = 2019
10055 measured reflections
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.102H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0372P)2 + 0.0108P]
where P = (Fo2 + 2Fc2)/3
2466 reflections(Δ/σ)max < 0.001
160 parametersΔρmax = 0.26 e Å3
0 restraintsΔρmin = 0.38 e Å3
Crystal data top
[Ni(C5O5)(C10H8N2)2]V = 2152.6 (15) Å3
Mr = 511.13Z = 4
Orthorhombic, PbcnMo Kα radiation
a = 12.725 (5) ŵ = 0.95 mm1
b = 10.752 (5) ÅT = 293 K
c = 15.733 (5) Å0.20 × 0.19 × 0.10 mm
Data collection top
Bruker APEXII CCD
diffractometer
2466 independent reflections
Absorption correction: multi-scan
(APEX2; Bruker, 2005)
1536 reflections with I > 2σ(I)
Tmin = 0.821, Tmax = 0.902Rint = 0.089
10055 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.102H-atom parameters constrained
S = 1.02Δρmax = 0.26 e Å3
2466 reflectionsΔρmin = 0.38 e Å3
160 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
xyzUiso*/Ueq
Ni10.50000.46011 (4)0.25000.03546 (17)
O10.56048 (15)0.31353 (15)0.17633 (10)0.0439 (5)
O20.6016 (2)0.0512 (2)0.12408 (16)0.1053 (10)
O30.50000.1097 (3)0.25000.0700 (9)
N10.45364 (18)0.58822 (19)0.34037 (12)0.0397 (5)
N20.63184 (17)0.46676 (19)0.32573 (12)0.0419 (6)
C10.3650 (3)0.6535 (3)0.34092 (17)0.0531 (8)
H10.31730.64100.29700.064*
C20.3402 (3)0.7384 (3)0.4029 (2)0.0717 (10)
H20.27740.78240.40130.086*
C30.4114 (4)0.7561 (3)0.4673 (2)0.0742 (11)
H30.39770.81420.50970.089*
C40.5025 (3)0.6888 (3)0.46926 (18)0.0570 (9)
H40.55020.69890.51350.068*
C50.5226 (2)0.6052 (2)0.40425 (15)0.0406 (7)
C60.6200 (2)0.5320 (2)0.39824 (16)0.0431 (7)
C70.6964 (3)0.5264 (3)0.4613 (2)0.0638 (9)
H70.68720.56960.51190.077*
C80.7854 (3)0.4569 (4)0.4486 (2)0.0770 (12)
H80.83670.45260.49060.092*
C90.7982 (2)0.3940 (3)0.3737 (2)0.0679 (10)
H90.85870.34790.36330.081*
C100.7195 (2)0.4008 (3)0.31437 (19)0.0575 (8)
H100.72760.35720.26370.069*
C110.5300 (2)0.2129 (3)0.21214 (15)0.0393 (6)
C120.5511 (3)0.0864 (3)0.18605 (18)0.0530 (8)
C130.50000.0035 (4)0.25000.0487 (10)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.0404 (3)0.0388 (3)0.0271 (2)0.0000.0053 (2)0.000
O10.0587 (13)0.0418 (11)0.0310 (9)0.0040 (10)0.0083 (9)0.0013 (8)
O20.167 (3)0.0586 (15)0.0903 (17)0.0026 (15)0.0769 (19)0.0177 (13)
O30.086 (2)0.0405 (17)0.084 (2)0.0000.0118 (18)0.000
N10.0510 (14)0.0360 (12)0.0322 (11)0.0008 (12)0.0020 (11)0.0015 (10)
N20.0437 (14)0.0480 (14)0.0340 (12)0.0003 (12)0.0082 (10)0.0017 (10)
C10.064 (2)0.0507 (18)0.0443 (16)0.0138 (17)0.0003 (16)0.0011 (14)
C20.098 (3)0.057 (2)0.060 (2)0.024 (2)0.022 (2)0.0018 (17)
C30.119 (3)0.048 (2)0.056 (2)0.002 (2)0.028 (2)0.0121 (16)
C40.084 (2)0.0514 (17)0.0359 (15)0.022 (2)0.0095 (16)0.0076 (13)
C50.0582 (19)0.0341 (14)0.0295 (13)0.0130 (14)0.0012 (12)0.0026 (11)
C60.0535 (18)0.0442 (16)0.0317 (14)0.0198 (15)0.0080 (13)0.0070 (13)
C70.076 (2)0.068 (2)0.0482 (18)0.023 (2)0.0272 (17)0.0038 (15)
C80.065 (2)0.090 (3)0.076 (3)0.023 (2)0.041 (2)0.033 (2)
C90.0442 (18)0.080 (3)0.079 (2)0.0036 (19)0.0144 (18)0.026 (2)
C100.0494 (19)0.067 (2)0.0555 (19)0.0078 (18)0.0081 (15)0.0055 (16)
C110.0431 (17)0.0439 (16)0.0309 (13)0.0025 (14)0.0005 (11)0.0019 (12)
C120.066 (2)0.0462 (17)0.0463 (17)0.0038 (17)0.0129 (16)0.0085 (14)
C130.052 (2)0.042 (2)0.052 (2)0.0000.000 (2)0.000
Geometric parameters (Å, º) top
Ni1—N22.059 (2)C3—C41.367 (4)
Ni1—N2i2.059 (2)C3—H30.9300
Ni1—N12.066 (2)C4—C51.385 (4)
Ni1—N1i2.066 (2)C4—H40.9300
Ni1—O1i2.1022 (18)C5—C61.472 (4)
Ni1—O12.1022 (18)C6—C71.389 (4)
O1—C111.280 (3)C7—C81.371 (5)
O2—C121.227 (3)C7—H70.9300
O3—C131.217 (5)C8—C91.369 (5)
N1—C11.328 (3)C8—H80.9300
N1—C51.347 (3)C9—C101.370 (4)
N2—C101.334 (3)C9—H90.9300
N2—C61.347 (3)C10—H100.9300
C1—C21.372 (4)C11—C11i1.415 (5)
C1—H10.9300C11—C121.446 (4)
C2—C31.373 (5)C12—C131.493 (4)
C2—H20.9300C13—C12i1.493 (4)
N2—Ni1—N2i176.02 (12)C3—C4—C5118.9 (3)
N2—Ni1—N179.12 (9)C3—C4—H4120.6
N2i—Ni1—N198.19 (8)C5—C4—H4120.6
N2—Ni1—N1i98.19 (8)N1—C5—C4121.3 (3)
N2i—Ni1—N1i79.12 (9)N1—C5—C6115.4 (2)
N1—Ni1—N1i96.35 (11)C4—C5—C6123.3 (3)
N2—Ni1—O1i90.30 (8)N2—C6—C7120.2 (3)
N2i—Ni1—O1i92.68 (8)N2—C6—C5115.3 (2)
N1—Ni1—O1i90.91 (8)C7—C6—C5124.5 (3)
N1i—Ni1—O1i169.72 (7)C8—C7—C6119.8 (3)
N2—Ni1—O192.68 (8)C8—C7—H7120.1
N2i—Ni1—O190.30 (8)C6—C7—H7120.1
N1—Ni1—O1169.72 (7)C9—C8—C7119.5 (3)
N1i—Ni1—O190.91 (8)C9—C8—H8120.2
O1i—Ni1—O182.88 (10)C7—C8—H8120.2
C11—O1—Ni1106.29 (15)C8—C9—C10118.2 (3)
C1—N1—C5118.5 (2)C8—C9—H9120.9
C1—N1—Ni1126.82 (19)C10—C9—H9120.9
C5—N1—Ni1114.72 (18)N2—C10—C9123.2 (3)
C10—N2—C6118.9 (2)N2—C10—H10118.4
C10—N2—Ni1125.83 (19)C9—C10—H10118.4
C6—N2—Ni1114.66 (19)O1—C11—C11i122.26 (14)
N1—C1—C2123.5 (3)O1—C11—C12127.9 (2)
N1—C1—H1118.3C11i—C11—C12109.83 (15)
C2—C1—H1118.3O2—C12—C11127.8 (3)
C1—C2—C3117.7 (3)O2—C12—C13125.4 (3)
C1—C2—H2121.1C11—C12—C13106.8 (2)
C3—C2—H2121.1O3—C13—C12i126.64 (17)
C4—C3—C2120.2 (3)O3—C13—C12126.64 (17)
C4—C3—H3119.9C12i—C13—C12106.7 (3)
C2—C3—H3119.9
N2—Ni1—O1—C1190.49 (17)C1—N1—C5—C6178.6 (2)
N2i—Ni1—O1—C1192.14 (18)Ni1—N1—C5—C61.2 (3)
N1—Ni1—O1—C1153.7 (5)C3—C4—C5—N11.0 (4)
N1i—Ni1—O1—C11171.27 (17)C3—C4—C5—C6177.3 (3)
O1i—Ni1—O1—C110.52 (13)C10—N2—C6—C72.5 (4)
N2—Ni1—N1—C1174.7 (2)Ni1—N2—C6—C7169.1 (2)
N2i—Ni1—N1—C12.3 (2)C10—N2—C6—C5178.1 (2)
N1i—Ni1—N1—C177.5 (2)Ni1—N2—C6—C510.3 (3)
O1i—Ni1—N1—C195.2 (2)N1—C5—C6—N26.1 (3)
O1—Ni1—N1—C1147.8 (4)C4—C5—C6—N2172.3 (2)
N2—Ni1—N1—C55.04 (17)N1—C5—C6—C7173.3 (2)
N2i—Ni1—N1—C5177.93 (18)C4—C5—C6—C78.3 (4)
N1i—Ni1—N1—C5102.20 (19)N2—C6—C7—C81.8 (4)
O1i—Ni1—N1—C585.09 (18)C5—C6—C7—C8178.8 (3)
O1—Ni1—N1—C532.5 (5)C6—C7—C8—C90.2 (5)
N1—Ni1—N2—C10179.3 (2)C7—C8—C9—C101.5 (5)
N1i—Ni1—N2—C1085.7 (2)C6—N2—C10—C91.2 (4)
O1i—Ni1—N2—C1088.5 (2)Ni1—N2—C10—C9169.4 (2)
O1—Ni1—N2—C105.6 (2)C8—C9—C10—N20.8 (5)
N1—Ni1—N2—C68.43 (17)Ni1—O1—C11—C11i1.5 (4)
N1i—Ni1—N2—C6103.37 (17)Ni1—O1—C11—C12179.9 (2)
O1i—Ni1—N2—C682.44 (17)O1—C11—C12—O20.7 (5)
O1—Ni1—N2—C6165.32 (17)C11i—C11—C12—O2179.3 (3)
C5—N1—C1—C20.6 (4)O1—C11—C12—C13178.9 (2)
Ni1—N1—C1—C2179.1 (2)C11i—C11—C12—C130.3 (4)
N1—C1—C2—C30.1 (5)O2—C12—C13—O30.6 (4)
C1—C2—C3—C41.2 (5)C11—C12—C13—O3179.89 (13)
C2—C3—C4—C51.7 (5)O2—C12—C13—C12i179.4 (4)
C1—N1—C5—C40.1 (4)C11—C12—C13—C12i0.11 (13)
Ni1—N1—C5—C4179.63 (19)
Symmetry code: (i) x+1, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O1ii0.932.573.340 (4)141
C8—H8···O2iii0.932.243.114 (4)156
C9—H9···O3iv0.932.573.222 (4)127
Symmetry codes: (ii) x, y+1, z+1/2; (iii) x+3/2, y+1/2, z+1/2; (iv) x+1/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula[Ni(C5O5)(C10H8N2)2]
Mr511.13
Crystal system, space groupOrthorhombic, Pbcn
Temperature (K)293
a, b, c (Å)12.725 (5), 10.752 (5), 15.733 (5)
V3)2152.6 (15)
Z4
Radiation typeMo Kα
µ (mm1)0.95
Crystal size (mm)0.20 × 0.19 × 0.10
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(APEX2; Bruker, 2005)
Tmin, Tmax0.821, 0.902
No. of measured, independent and
observed [I > 2σ(I)] reflections
10055, 2466, 1536
Rint0.089
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.102, 1.02
No. of reflections2466
No. of parameters160
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.26, 0.38

Computer programs: APEX2 (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O1i0.932.573.340 (4)140.7
C8—H8···O2ii0.932.243.114 (4)155.8
C9—H9···O3iii0.932.573.222 (4)127.3
Symmetry codes: (i) x, y+1, z+1/2; (ii) x+3/2, y+1/2, z+1/2; (iii) x+1/2, y+1/2, z+1/2.
 

Acknowledgements

This work was supported by the PhD Foundation of the Ministry of Education of China and by the National Natural Science Foundation of China (grant No. 50673054).

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