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

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ISSN: 2056-9890
Volume 69| Part 2| February 2013| Pages m129-m130

Bis(3-amino­pyrazine-2-carboxyl­ato-κ2N1,O)di­aqua­cobalt(II)

aLaboratoire de Chimie Appliquée et Technologie des Matériaux LCATM, Université Oum El Bouaghi, Algeria, bDépartement Sciences de la Matière, Faculté des Sciences Exactes et Sciences de la Nature et de la Vie, Université Oum El Bouaghi, Algeria, and cUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Faculté des Sciences Exactes, Université Mentouri Constantine 25000, Algeria
*Correspondence e-mail: bouacida_sofiane@yahoo.fr

(Received 17 January 2013; accepted 22 January 2013; online 31 January 2013)

In the title compound, [Co(C5H4N3O2)2(H2O)2], the CoII atom is situated on a twofold rotation axis and is N,O-chelated by two 3-amino­pyrazine-2-carboxyl­ate anions and additionally bonded to the O atoms of two water mol­ecules, leading to a slightly distorted octa­hedral coordination environment. The crystal packing is dominated by inter­molecular O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonding involving the water mol­ecules and amino groups as donors and carboxyl­ate O atoms, as well as the non-coordinating heterocyclic N atoms as acceptors, resulting in a three-dimensional network. An intra­molecular N—H⋯O hydrogen bond is also observed.

Related literature

For the role of N,O-coordination in the crystal structures of metal complexes with pyrazine-2-carboxyl­ate as ligand, see: Alcock et al. (1996[Alcock, N. W., Kemp, T. J., Marc Roe, S. & Leciejewicz, J. (1996). Inorg. Chim. Acta, 248, 241-246.]); Dong et al. (2000[Dong, Y.-B., Smith, M. D. & zur Loye, H.-C. (2000). Inorg. Chem. 39, 1943-1949.]); Kubota et al. (2006[Kubota, Y., Takata, M., Matsuda, R., Kitaura, R., Kitagawa, S. & Kobayashi, T. C. (2006). Angew. Chem. Int. Ed. 45, 4932-4936.]); Luo et al. (2004[Luo, J., Alexander, B., Wagner, T. R. & Maggard, P. A. (2004). Inorg. Chem. 43, 5537-5542.]). For related pyrazine-2-carboxyl­ate cobalt(II) complexes and their applications, see: Fan et al. (2007[Fan, G., Chen, S.-P. & Gao, S.-L. (2007). Acta Cryst. E63, m772-m773.]); Liu et al. (2007[Liu, F.-Y., Shang, R.-L., Du, L., Zhao, Q.-H. & Fang, R.-B. (2007). Acta Cryst. E63, m120-m122.]); McCleverty & Meyer (2004[McCleverty, J. A. & Meyer, T. J. (2004). Comprehensive Coordination Chemistry II. From Biology to Nanotechnology, Vol. 6, Transition Metal Groups 9-12, pp. 99-120. Amsterdam: Elsevier Pergamon.]); Shi et al. (2011[Shi, Q.-Y., Zhang, G.-C., Zhou, C.-S. & Yang, Q. (2011). Acta Cryst. E67, m1430.]); Sun et al. (2004[Sun, W.-H., Tang, X., Gao, T., Wu, B., Zhang, W. & Ma, H. (2004). Organometallics, 23, 5037-5041.]); Tanase et al. (2006[Tanase, S., Martin, V. S., Van Albada, G. A., DeGelder, R., Bouwman, E. & Reedijk, J. (2006). Polyhedron, 25, 2967-2975.]). For the influence of hydrogen bonding in related systems, see: Bouacida et al. (2007[Bouacida, S., Merazig, H., Benard-Rocherulle, P. & Rizzoli, C. (2007). Acta Cryst. E63, m379-m381.], 2009[Bouacida, S., Belhouas, R., Kechout, H., Merazig, H. & Bénard-Rocherullé, P. (2009). Acta Cryst. E65, o628-o629.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(C5H4N3O2)2(H2O)2]

  • Mr = 371.19

  • Monoclinic, C 2/c

  • a = 7.8823 (2) Å

  • b = 12.7467 (2) Å

  • c = 13.6851 (3) Å

  • β = 91.918 (1)°

  • V = 1374.22 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.29 mm−1

  • T = 295 K

  • 0.11 × 0.09 × 0.05 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • 17706 measured reflections

  • 4800 independent reflections

  • 3043 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.082

  • S = 0.92

  • 4800 reflections

  • 111 parameters

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

  • Δρmax = 0.48 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
O1W—H1W⋯N2i 0.761 (18) 2.070 (18) 2.8254 (12) 172.2 (17)
O1W—H2W⋯O52ii 0.762 (18) 1.898 (17) 2.6470 (12) 167.1 (16)
N3—H3A⋯O51iii 0.86 2.33 3.0525 (12) 141
N3—H3B⋯O52 0.86 2.07 2.7036 (13) 130
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) [x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]; (iii) [x, -y, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2011[Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2011[Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SIR2002 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg & Berndt, 2001[Brandenburg, K. & Berndt, M. (2001). DIAMOND. Crystal Impact, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

During our recent research in the field of N,O-donor stabilized metal complexes we have prepared the title compound. As ligand we have chosen pyrazine-2-carboxylate that already has been extensively studied (Alcock et al., 1996; Dong et al., 2000; Kubota et al., 2006; Luo et al., 2004; Shi et al., 2011; Fan et al., 2007; Liu et al., 2007). Some of its cobalt(II) complexes have also been reported for multitude applications (Tanase et al., 2006; Sun et al., 2004; McCleverty & Meyer, 2004).

In continuation of our investigations on the influence of hydrogen bonds on the structural features (Bouacida et al., 2007,2009), we report here the crystal growth and crystal structure of the title compound, [Co(C5H4N3O2)2(H2O)2] (I).

The asymmetric unit of (I) consists of one-half of the complex molecule, with the other half being generated by a twofold rotation axis running through the CoII atom (Wyckoff site 4 e). The latter is octahedrally coordinated by two 3-aminopyrazine-2-carboxylate anions acting in a bidentate manner and by two water molecules. The molecular geometry and the atom-numbering scheme of (I) are shown in Fig. 1.

Bond lengths and angles observed in the different entities show normal features and are consistent with those reported previously for related systems (Shi et al., 2011). Fig. 2 shows a packing diagram of the structure. Parallel to the c axis channels with a square cross-section are formed. The crystal packing can be described by stacking of alternating layers parallel to (110). The layers are linked together by O1W—H···N, O1W—H···O and N—H···O interactions involving the water molecules and amino functions as donors and carboxylate O atoms as well as the non-coordinating heterocyclic N atoms as acceptors (Fig. 3, Table 1). These interactions lead to the formation of a three-dimensional network.

Related literature top

For the role of N,O-coordination in the crystal structures of metal complexes with pyrazine-2-carboxylate as ligand, see: Alcock et al. (1996); Dong et al. (2000); Kubota et al. (2006); Luo et al. (2004). For related pyrazine-2-carboxylate cobalt(II) complexes and their applications, see: Fan et al. (2007); Liu et al. (2007); McCleverty & Meyer (2004); Shi et al. (2011); Sun et al. (2004); Tanase et al. (2006). For the influence of hydrogen bonding in related systems, see: Bouacida et al. (2007, 2009).

Experimental top

The title compound was obtained from a mixture of cobalt(II) chloride hexahydrate (0.05 g, 0.2 mmol), 3-aminopyrazine-2-carboxylic acid (0.03 g, 0.2 mmol) and acidified water (25 ml, HCl 37%). The solution was evaporated at room temperature for two weeks. Yellow single crystals were obtained and were carefully isolated under a polarizing microscope for analysis by X-ray diffraction.

Refinement top

The H atoms were localized in Fourier maps but were eventually introduced in calculated positions and treated as riding on their parent atoms (C or N) with C—H = 0.93 Å and N—H = 0.86 Å with Uiso(H) = 1.2Ueq(C or N). The water H atoms H1W and H2W were also located in a difference Fourier map. Their positions were refined freely, but their temperature factors were refined isotropically with Uiso(H) = 1.5Ueq(OW).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SIR2002 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg & Berndt, 2001); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. A view of the coordination environment of the CoII atom of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radius. [Symmetry code: (i)-x, y, -z + 3/2.]
[Figure 2] Fig. 2. The packing of the structure of (I) viewed along the c axis
[Figure 3] Fig. 3. Hydrogen bonding interactions (dashed lines) in the structure of (I)
Bis(3-aminopyrazine-2-carboxylato-κ2N1,O)diaquacobalt(II) top
Crystal data top
[Co(C5H4N3O2)2(H2O)2]F(000) = 756
Mr = 371.19Dx = 1.794 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
a = 7.8823 (2) ÅCell parameters from 6448 reflections
b = 12.7467 (2) Åθ = 3.0–38.7°
c = 13.6851 (3) ŵ = 1.29 mm1
β = 91.918 (1)°T = 295 K
V = 1374.22 (5) Å3Block, yellow
Z = 40.11 × 0.09 × 0.05 mm
Data collection top
Bruker APEXII CCD
diffractometer
3043 reflections with I > 2σ(I)
Radiation source: sealed tubeRint = 0.041
Graphite monochromatorθmax = 42.1°, θmin = 3.0°
ϕ and ω scansh = 1410
17706 measured reflectionsk = 2422
4800 independent reflectionsl = 2516
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)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.082H atoms treated by a mixture of independent and constrained refinement
S = 0.92 w = 1/[σ2(Fo2) + (0.0413P)2]
where P = (Fo2 + 2Fc2)/3
4800 reflections(Δ/σ)max = 0.001
111 parametersΔρmax = 0.48 e Å3
0 restraintsΔρmin = 0.38 e Å3
Crystal data top
[Co(C5H4N3O2)2(H2O)2]V = 1374.22 (5) Å3
Mr = 371.19Z = 4
Monoclinic, C2/cMo Kα radiation
a = 7.8823 (2) ŵ = 1.29 mm1
b = 12.7467 (2) ÅT = 295 K
c = 13.6851 (3) Å0.11 × 0.09 × 0.05 mm
β = 91.918 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
3043 reflections with I > 2σ(I)
17706 measured reflectionsRint = 0.041
4800 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0340 restraints
wR(F2) = 0.082H atoms treated by a mixture of independent and constrained refinement
S = 0.92Δρmax = 0.48 e Å3
4800 reflectionsΔρmin = 0.38 e Å3
111 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
Co100.195326 (13)0.750.02207 (5)
O1W0.19025 (11)0.30652 (6)0.76033 (6)0.03609 (17)
H1W0.250 (2)0.3194 (11)0.7195 (13)0.054*
H2W0.1779 (19)0.3585 (14)0.7867 (12)0.054*
O510.18087 (10)0.07591 (6)0.76347 (5)0.03603 (17)
O520.31276 (13)0.02336 (7)0.87118 (6)0.0538 (2)
N10.03120 (10)0.18853 (6)0.90389 (5)0.02230 (13)
N20.09937 (11)0.16410 (8)1.09943 (6)0.03211 (17)
C10.04090 (12)0.25148 (8)0.97172 (6)0.02822 (18)
H10.11640.30350.95350.034*
N30.26554 (13)0.02032 (8)1.06349 (7)0.0453 (2)
H3A0.28270.01381.12490.054*
H3B0.31120.02321.02240.054*
C20.00267 (13)0.23880 (9)1.06893 (7)0.0327 (2)
H20.05080.28471.11480.039*
C30.16811 (12)0.09790 (7)1.03189 (7)0.02792 (18)
C40.13532 (11)0.11308 (7)0.93095 (6)0.02309 (15)
C50.21616 (13)0.04957 (8)0.84893 (7)0.03098 (19)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.02920 (9)0.02103 (9)0.01636 (7)00.00654 (5)0
O1W0.0437 (4)0.0371 (4)0.0284 (3)0.0159 (3)0.0152 (3)0.0072 (3)
O510.0514 (4)0.0342 (4)0.0230 (3)0.0146 (3)0.0090 (3)0.0052 (3)
O520.0808 (6)0.0417 (5)0.0405 (4)0.0356 (4)0.0263 (4)0.0128 (4)
N10.0249 (3)0.0230 (3)0.0193 (3)0.0009 (3)0.0057 (2)0.0015 (2)
N20.0378 (4)0.0383 (4)0.0207 (3)0.0010 (4)0.0071 (3)0.0019 (3)
C10.0285 (4)0.0338 (5)0.0225 (4)0.0058 (4)0.0025 (3)0.0005 (3)
N30.0686 (7)0.0378 (5)0.0307 (4)0.0167 (5)0.0196 (4)0.0032 (4)
C30.0343 (4)0.0259 (4)0.0242 (4)0.0031 (3)0.0112 (3)0.0041 (3)
C50.0410 (5)0.0242 (4)0.0284 (4)0.0072 (4)0.0117 (4)0.0050 (3)
C40.0285 (4)0.0202 (4)0.0210 (3)0.0010 (3)0.0083 (3)0.0014 (3)
C20.0348 (5)0.0411 (6)0.0221 (4)0.0031 (4)0.0007 (3)0.0024 (4)
Geometric parameters (Å, º) top
Co1—O1W2.0648 (8)N1—C11.3390 (11)
Co1—O1Wi2.0648 (8)N2—C21.3230 (14)
Co1—O512.0979 (7)N2—C31.3515 (13)
Co1—O51i2.0979 (7)C1—C21.3834 (13)
Co1—N1i2.1303 (7)C1—H10.93
Co1—N12.1303 (7)N3—C31.3329 (13)
O1W—H1W0.760 (18)N3—H3A0.86
O1W—H2W0.763 (18)N3—H3B0.86
O51—C51.2568 (12)C3—C41.4270 (12)
O52—C51.2460 (12)C5—C41.5078 (13)
N1—C41.3252 (11)C2—H20.93
O1W—Co1—O1Wi93.31 (5)C1—N1—Co1126.91 (6)
O1W—Co1—O51170.46 (3)C2—N2—C3117.88 (8)
O1Wi—Co1—O5190.57 (4)N1—C1—C2119.71 (9)
O1W—Co1—O51i90.57 (4)N1—C1—H1120.1
O1Wi—Co1—O51i170.46 (3)C2—C1—H1120.1
O51—Co1—O51i86.97 (5)C3—N3—H3A120
O1W—Co1—N1i89.31 (3)C3—N3—H3B120
O1Wi—Co1—N1i93.89 (3)H3A—N3—H3B120
O51—Co1—N1i99.13 (3)N3—C3—N2117.61 (8)
O51i—Co1—N1i77.43 (3)N3—C3—C4122.66 (9)
O1W—Co1—N193.89 (3)N2—C3—C4119.73 (8)
O1Wi—Co1—N189.31 (3)O52—C5—O51125.65 (9)
O51—Co1—N177.43 (3)O52—C5—C4117.72 (8)
O51i—Co1—N199.13 (3)O51—C5—C4116.63 (8)
N1i—Co1—N1175.34 (4)N1—C4—C3120.19 (8)
Co1—O1W—H1W124.2 (12)N1—C4—C5115.59 (7)
Co1—O1W—H2W121.7 (11)C3—C4—C5124.20 (8)
H1W—O1W—H2W104.7 (15)N2—C2—C1122.81 (9)
C5—O51—Co1116.60 (6)N2—C2—H2118.6
C4—N1—C1119.58 (7)C1—C2—H2118.6
C4—N1—Co1113.50 (6)
O1Wi—Co1—O51—C593.84 (8)Co1—O51—C5—O52175.74 (10)
O51i—Co1—O51—C595.39 (8)Co1—O51—C5—C44.97 (12)
N1i—Co1—O51—C5172.13 (8)C1—N1—C4—C31.05 (13)
N1—Co1—O51—C54.67 (7)Co1—N1—C4—C3179.46 (6)
O1W—Co1—N1—C4172.54 (6)C1—N1—C4—C5177.36 (8)
O1Wi—Co1—N1—C494.19 (6)Co1—N1—C4—C52.13 (10)
O51—Co1—N1—C43.45 (6)N3—C3—C4—N1176.88 (9)
O51i—Co1—N1—C481.34 (6)N2—C3—C4—N13.34 (13)
O1W—Co1—N1—C18.01 (8)N3—C3—C4—C54.85 (15)
O1Wi—Co1—N1—C185.25 (8)N2—C3—C4—C5174.93 (9)
O51—Co1—N1—C1175.99 (8)O52—C5—C4—N1178.82 (10)
O51i—Co1—N1—C199.22 (8)O51—C5—C4—N11.84 (13)
C4—N1—C1—C21.63 (14)O52—C5—C4—C32.84 (15)
Co1—N1—C1—C2177.78 (7)O51—C5—C4—C3176.50 (9)
C2—N2—C3—N3177.46 (9)C3—N2—C2—C10.07 (16)
C2—N2—C3—C42.76 (14)N1—C1—C2—N22.23 (16)
Symmetry code: (i) x, y, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···N2ii0.761 (18)2.070 (18)2.8254 (12)172.2 (17)
O1W—H2W···O52iii0.762 (18)1.898 (17)2.6470 (12)167.1 (16)
N3—H3A···O51iv0.862.333.0525 (12)141
N3—H3B···O520.862.072.7036 (13)130
C1—H1···O52iii0.932.553.4010 (13)153
Symmetry codes: (ii) x+1/2, y+1/2, z1/2; (iii) x+1/2, y+1/2, z; (iv) x, y, z+1/2.

Experimental details

Crystal data
Chemical formula[Co(C5H4N3O2)2(H2O)2]
Mr371.19
Crystal system, space groupMonoclinic, C2/c
Temperature (K)295
a, b, c (Å)7.8823 (2), 12.7467 (2), 13.6851 (3)
β (°) 91.918 (1)
V3)1374.22 (5)
Z4
Radiation typeMo Kα
µ (mm1)1.29
Crystal size (mm)0.11 × 0.09 × 0.05
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
17706, 4800, 3043
Rint0.041
(sin θ/λ)max1)0.944
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.082, 0.92
No. of reflections4800
No. of parameters111
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.48, 0.38

Computer programs: APEX2 (Bruker, 2011), SAINT (Bruker, 2011), SIR2002 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg & Berndt, 2001), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···N2i0.761 (18)2.070 (18)2.8254 (12)172.2 (17)
O1W—H2W···O52ii0.762 (18)1.898 (17)2.6470 (12)167.1 (16)
N3—H3A···O51iii0.86002.33003.0525 (12)141.00
N3—H3B···O520.86002.07002.7036 (13)130.00
Symmetry codes: (i) x+1/2, y+1/2, z1/2; (ii) x+1/2, y+1/2, z; (iii) x, y, z+1/2.
 

Acknowledgements

We are grateful to the personal of the LCATM laboratory, Université Oum El Bouaghi, Algeria, for their assistance. Thanks are due to the MESRS and ATRST (Ministére de l'Enseignement Supérieur et de la Recherche Scientifique et l'Agence thématique de recherche en sciences et technologie - Algérie) via the PNR programm for financial support.

References

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Volume 69| Part 2| February 2013| Pages m129-m130
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