Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Previous article
Next article
Previous article
Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Next article

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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 1| January 2008| Page m13
https://doi.org/10.1107/S1600536807061491

Di­bromidobis(pyrazine-2-carboxylic acid-κN4)mercury(II) dihydrate

Guo-Wei Wang,a* Wen-Yuan Wu,a Ling-Hua Zhuanga and Jin-Tang Wanga

aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, Nanjing 210009, People's Republic of China
*Correspondence e-mail: kingwell2004@sina.com.cn

(Received 2 November 2007; accepted 21 November 2007; online 6 December 2007)

The asymmetric unit of the title compound, [HgBr2(C5H4N2O2)2]·2H2O, contains one half-mol­ecule and one water mol­ecule. The HgII ion, lying on a twofold rotation axis, is four-coordinated by two N atoms of pyrazine-2-carboxylic acid ligands and two bromide ions, forming a highly distorted tetrahedral geometry. In the crystal structure, inter­molecular O—H⋯O and O—H⋯N hydrogen bonds link the mol­ecules.

Related literature

For general background, see: O'Conner et al. (1982[O'Conner, C. J., Klein, C. L., Majeste, R. J. & Trefonas, L. M. (1982). Inorg. Chem. 21, 64-67.]); Zhang (2005[Zhang, B.-S. (2005). Chin. J. Struct. Chem. 24, 478-482.]); Zou et al. (1999[Zou, J.-Z., Xu, Z., Chen, W., Lo, K. M. & You, X.-Z. (1999). Polyhedron, 18, 1507-1512.]). For a related structure, see: Wang et al.(2007[Wang, X.-F., Lv, Y., Okamura, T., Kawaguchi, H., Wu, G., Sun, W.-Y. & Ueyama, N. (2007). Cryst. Growth Des. 7, 1125-1133.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data

  • [HgBr2(C5H4N2O2)2]·2H2O

  • Mr = 644.63

  • Monoclinic, C 2/c

  • a = 13.895 (1) Å

  • b = 5.7176 (2) Å

  • c = 21.8753 (7) Å

  • β = 102.544 (2)°

  • V = 1696.42 (15) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 13.82 mm−1

  • T = 294 (2) K

  • 0.4 × 0.2 × 0.2 mm
Data collection

  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.048, Tmax = 0.063

  • 2775 measured reflections

  • 1480 independent reflections

  • 1287 reflections with I > 2σ(I)

  • Rint = 0.062

  • 3 standard reflections every 200 reflections intensity decay: none
Refinement

  • R[F2 > 2σ(F2)] = 0.070

  • wR(F2) = 0.150

  • S = 1.12

  • 1480 reflections

  • 112 parameters

  • 2 restraints

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

  • Δρmax = 2.85 e Å−3

  • Δρmin = −3.62 e Å−3

Table 1
Selected geometric parameters (Å, °)

Hg1—Br1 2.4234 (15)
Hg1—N1 2.528 (13)
Br1—Hg1—Br1i 153.72 (12)
Br1—Hg1—N1 97.8 (3)
Br1i—Hg1—N1 101.2 (3)
N1—Hg1—N1i 86.9 (6)
Symmetry code: (i) [-x+2, y, -z+{\script{3\over 2}}].

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O2—H2A⋯O3ii 0.82 1.75 2.56 (2) 166
O3—H3A⋯O1iii 0.84 (2) 2.28 (3) 2.89 (2) 130 (2)
O3—H3B⋯N2 0.84 (2) 2.09 (3) 2.93 (2) 177 (3)
Symmetry codes: (ii) -x+2, -y, -z+1; (iii) [x-{\script{1\over 2}}, y-{\script{1\over 2}}, z].

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Version 5.0. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: SHELXTL (Bruker, 2000[Bruker (2000). SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536807061491/hk2365sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807061491/hk2365Isup2.hkl

checkCIF report


Comment top

Functional materials built up by organic ligands and metal ions, especially transition metals, have potential applications in optics, electronics, magnetics, biology, catalyst and medicine (Zhang, 2005; O'Conner et al., 1982). Pyrazine-2,3-dicarboxylic acid, having six possible coordination sites, is a good ligand with versatile coordination types, which is widely used in the self-assembled polymeric coordination synthesis (Zou et al., 1999; Wang et al., 2007). The title compound, (I), was obtained unintentionally as the product of a hydrothermal synthesis of pyrazine-2,3-dicarboxylic acid and mercury(II) bromide. Under high temperature as 413 K and mercury(II) ion catalyst, pyrazine-2,3-dicarboxylic acid is likely to decarboxylate as 2-pyrazine carboxylic acid. We report herein the crystal structure of (I), a complex containing the ligand of 2-pyrazine carboxylic acid.

The asymmetric unit of (I), (Fig. 1), contains one half-molecule and one water molecule, in which the bond lengths and angles are within normal ranges (Allen et al., 1987). The HgII ion lying on a twofold rotation axis, is four -coordinated (Table 1) by two N atoms of pyrazine carboxylic acid ligands and two bromide atoms. The two pyrazine rings are oriented at a dihedral angle of 78.4 (9)°.

The Hg—N [2.528 (13) Å] bond is slightly longer, while Hg—Br [2.4234 (15) Å] bond is slightly shorter than the corresponding values [2.270 (5) Å and 2.5269 (7) Å, respectively] in [Hg(bib)Br2]0.5THF (where bib is 1-bromo-3,5 -bis(imidazol-1-ylmethyl)benzene) (Wang et al., 2007).

In the crystal structure, intermolecular O—H···O and O—H···N hydrogen bonds (Table 2, Fig. 2) link the molecules, in which they seem to be effective in the stabilization of the structure.

Related literature top

For general background, see: O'Conner et al. (1982); Zhang (2005); Zou et al. (1999). For related structure, see: Wang et al.(2007). For bond-length data, see: Allen et al. (1987).

Experimental top

For the preparation of the title compound, mercury(II) bromide (360 mg, 1 mmol) and 2,3-pyrazine dicarboxylic acid (168 mg, 1 mmol) were dissolved in a mixed solvent of ethanol (5 ml) and acetonitrile (5 ml). Then the mixture was added into a Teflon-lined stainless steel autoclave at 413 K for 2 d. The green crystals were obtained after cooling to room temperature and was filtrated. Elemental analysis calcd: C 19.58%, H 4.40%, N 45.60%; Found: C 19.51%, H 4.35%, N 45.53%.

Refinement top

H atoms (for H2O) were located in a difference map and refined [O—H = 0.84 (2) and 0.84 (2) Å, Uiso(H) = 1.5Ueq(O)]. The remaining H atoms were positioned geometrically, with O—H = 0.82 Å (for OH) and C—H = 0.93 Å, for aromatic H atoms and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C,O), where x = 1.2 for aromatic H and x = 1.5 for OH H atoms.

Structure description top

Functional materials built up by organic ligands and metal ions, especially transition metals, have potential applications in optics, electronics, magnetics, biology, catalyst and medicine (Zhang, 2005; O'Conner et al., 1982). Pyrazine-2,3-dicarboxylic acid, having six possible coordination sites, is a good ligand with versatile coordination types, which is widely used in the self-assembled polymeric coordination synthesis (Zou et al., 1999; Wang et al., 2007). The title compound, (I), was obtained unintentionally as the product of a hydrothermal synthesis of pyrazine-2,3-dicarboxylic acid and mercury(II) bromide. Under high temperature as 413 K and mercury(II) ion catalyst, pyrazine-2,3-dicarboxylic acid is likely to decarboxylate as 2-pyrazine carboxylic acid. We report herein the crystal structure of (I), a complex containing the ligand of 2-pyrazine carboxylic acid.

The asymmetric unit of (I), (Fig. 1), contains one half-molecule and one water molecule, in which the bond lengths and angles are within normal ranges (Allen et al., 1987). The HgII ion lying on a twofold rotation axis, is four -coordinated (Table 1) by two N atoms of pyrazine carboxylic acid ligands and two bromide atoms. The two pyrazine rings are oriented at a dihedral angle of 78.4 (9)°.

The Hg—N [2.528 (13) Å] bond is slightly longer, while Hg—Br [2.4234 (15) Å] bond is slightly shorter than the corresponding values [2.270 (5) Å and 2.5269 (7) Å, respectively] in [Hg(bib)Br2]0.5THF (where bib is 1-bromo-3,5 -bis(imidazol-1-ylmethyl)benzene) (Wang et al., 2007).

In the crystal structure, intermolecular O—H···O and O—H···N hydrogen bonds (Table 2, Fig. 2) link the molecules, in which they seem to be effective in the stabilization of the structure.

For general background, see: O'Conner et al. (1982); Zhang (2005); Zou et al. (1999). For related structure, see: Wang et al.(2007). For bond-length data, see: Allen et al. (1987).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Bruker, 2000).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level [symmetry code A: 2 - x, y, 3/2 - z]. Hydrogen bonds are shown as dashed lines.
[Figure 2] Fig. 2. A packing diagram of (I). Hydrogen bonds are shown as dashed lines.
Dibromidobis(pyrazine-2-carboxylic acid-κN4)mercury(II) dihydrate top
Crystal data top
[HgBr2(C5H4N2O2)2]·2H2OF(000) = 1192
Mr = 644.63Dx = 2.524 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 25 reflections
a = 13.895 (1) Åθ = 9–13°
b = 5.7176 (2) ŵ = 13.82 mm−1
c = 21.8753 (7) ÅT = 294 K
β = 102.544 (2)°Block, green
V = 1696.42 (15) Å30.4 × 0.2 × 0.2 mm
Z = 4
Data collection top
Enraf–Nonius CAD-4
diffractometer		1287 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.062
Graphite monochromatorθmax = 25.1°, θmin = 1.9°
ω/2θ scansh = −16→8
Absorption correction: ψ scan
(North et al., 1968)		k = −6→5
Tmin = 0.048, Tmax = 0.063l = −20→26
2775 measured reflections3 standard reflections every 200 reflections
1480 independent reflections intensity decay: none
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.070H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.150 w = 1/[σ2(Fo2) + (0.1015P)2 + 4.7441P]
where P = (Fo2 + 2Fc2)/3
S = 1.12(Δ/σ)max < 0.001
1480 reflectionsΔρmax = 2.85 e Å−3
112 parametersΔρmin = −3.62 e Å−3
2 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0045 (4)
Crystal data top
[HgBr2(C5H4N2O2)2]·2H2OV = 1696.42 (15) Å3
Mr = 644.63Z = 4
Monoclinic, C2/cMo Kα radiation
a = 13.895 (1) ŵ = 13.82 mm−1
b = 5.7176 (2) ÅT = 294 K
c = 21.8753 (7) Å0.4 × 0.2 × 0.2 mm
β = 102.544 (2)°
Data collection top
Enraf–Nonius CAD-4
diffractometer		1287 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.062
Tmin = 0.048, Tmax = 0.0633 standard reflections every 200 reflections
2775 measured reflections intensity decay: none
1480 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0702 restraints
wR(F2) = 0.150H atoms treated by a mixture of independent and constrained refinement
S = 1.12Δρmax = 2.85 e Å−3
1480 reflectionsΔρmin = −3.62 e Å−3
112 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
Hg11.00001.10939 (9)0.75000.0355 (4)
Br11.16422 (12)1.2057 (6)0.73701 (9)0.0525 (6)
C10.8717 (5)0.6941 (4)0.6566 (4)0.039 (4)
H10.82340.75610.67540.047*
C20.8499 (5)0.5080 (4)0.6166 (4)0.041 (4)
H20.78710.44270.60930.050*
C31.0047 (6)0.5069 (4)0.6006 (6)0.030 (3)
C41.0302 (6)0.6941 (6)0.6411 (6)0.043 (5)
H41.09400.75380.64900.051*
C51.0825 (6)0.4040 (4)0.5701 (5)0.029 (3)
N10.9628 (7)0.7881 (7)0.6688 (6)0.033 (3)
N20.9161 (7)0.4188 (7)0.5885 (5)0.034 (3)
O11.1642 (8)0.4862 (6)0.5761 (6)0.046 (3)
O21.0514 (10)0.2121 (5)0.5379 (6)0.060 (4)
H2A1.09540.16060.52210.090*
O30.8315 (9)0.0042 (3)0.5179 (6)0.051 (3)
H3A0.794 (2)−0.090 (3)0.531 (2)0.077*
H3B0.857 (2)0.123 (2)0.537 (2)0.077*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Hg10.0234 (5)0.0443 (7)0.0442 (6)0.0000.0149 (3)0.000
Br10.0263 (10)0.0587 (14)0.0617 (13)−0.0056 (8)0.0225 (9)0.0088 (10)
C10.029 (9)0.045 (10)0.047 (10)0.007 (8)0.017 (7)−0.011 (8)
C20.031 (8)0.050 (11)0.045 (10)0.000 (9)0.014 (7)−0.004 (9)
C30.027 (7)0.044 (10)0.021 (7)−0.011 (7)0.005 (6)0.003 (7)
C40.029 (8)0.051 (13)0.027 (8)0.004 (9)0.020 (7)−0.009 (8)
C50.035 (9)0.032 (8)0.033 (7)0.001 (7)0.012 (6)0.006 (7)
N10.037 (7)0.034 (8)0.032 (7)0.000 (6)0.012 (6)−0.012 (6)
N20.033 (6)0.053 (9)0.028 (6)−0.012 (6)0.002 (5)−0.008 (6)
O10.030 (6)0.054 (8)0.051 (7)−0.011 (6)0.016 (5)−0.020 (6)
O20.050 (8)0.061 (9)0.057 (9)−0.010 (7)0.033 (7)−0.039 (8)
O30.039 (7)0.052 (9)0.052 (9)−0.014 (7)0.033 (6)−0.030 (7)
Geometric parameters (Å, º) top
Hg1—Br12.4234 (15)C3—C41.381 (6)
Hg1—Br1i2.4234 (15)C3—C51.510 (7)
Hg1—N12.528 (13)C4—N11.334 (10)
Hg1—N1i2.528 (13)C4—H40.9300
C1—N11.351 (7)C5—O11.209 (18)
C1—C21.369 (8)C5—O21.327 (19)
C1—H10.9300O2—H2A0.8200
C2—N21.310 (6)O3—H3A0.84 (2)
C2—H20.9300O3—H3B0.84 (2)
C3—N21.303 (8)
Br1—Hg1—Br1i153.72 (12)C4—C3—C5118.4 (6)
Br1—Hg1—N197.8 (3)N1—C4—C3119.6 (7)
Br1i—Hg1—N1101.2 (3)N1—C4—H4120.2
Br1—Hg1—N1i101.2 (3)C3—C4—H4120.2
Br1i—Hg1—N1i97.8 (3)O1—C5—O2124.8 (7)
N1—Hg1—N1i86.9 (6)O1—C5—C3123.1 (8)
N1—C1—C2120.3 (8)O2—C5—C3112.1 (6)
N1—C1—H1119.8C1—N1—C4118.1 (7)
C2—C1—H1119.8C1—N1—Hg1118.0 (10)
N2—C2—C1121.3 (8)C4—N1—Hg1123.7 (11)
N2—C2—H2119.4C2—N2—C3118.7 (8)
C1—C2—H2119.4C5—O2—H2A109.5
N2—C3—C4122.0 (7)H3A—O3—H3B125 (4)
N2—C3—C5119.6 (8)
N1—C1—C2—N2−1.0 (12)C3—C4—N1—Hg1175.2 (12)
N2—C3—C4—N1−0.3 (13)Br1—Hg1—N1—C1−174.8 (12)
C5—C3—C4—N1−179.9 (15)Br1i—Hg1—N1—C1−13.0 (13)
N2—C3—C5—O1175.2 (15)N1i—Hg1—N1—C184.4 (13)
C4—C3—C5—O1−4.8 (12)Br1—Hg1—N1—C410.9 (13)
N2—C3—C5—O2−7.1 (11)Br1i—Hg1—N1—C4172.7 (13)
C4—C3—C5—O2173.3 (15)N1i—Hg1—N1—C4−89.9 (14)
C2—C1—N1—C40.3 (9)C1—C2—N2—C31.8 (12)
C2—C1—N1—Hg1−175.1 (5)C4—C3—N2—C2−1.1 (11)
C3—C4—N1—C11.2 (9)C5—C3—N2—C2178.5 (14)
Symmetry code: (i) −x+2, y, −z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2A···O3ii0.821.752.56 (2)166
O3—H3A···O1iii0.84 (2)2.28 (3)2.89 (2)130 (2)
O3—H3B···N20.84 (2)2.09 (3)2.93 (2)177 (3)
Symmetry codes: (ii) −x+2, −y, −z+1; (iii) x−1/2, y−1/2, z.

Experimental details

Crystal data
Chemical formula[HgBr2(C5H4N2O2)2]·2H2O
Mr644.63
Crystal system, space groupMonoclinic, C2/c
Temperature (K)294
a, b, c (Å)13.895 (1), 5.7176 (2), 21.8753 (7)
β (°) 102.544 (2)
V (Å3)1696.42 (15)
Z4
Radiation typeMo Kα
µ (mm−1)13.82
Crystal size (mm)0.4 × 0.2 × 0.2
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.048, 0.063
No. of measured, independent and
observed [I > 2σ(I)] reflections		2775, 1480, 1287
Rint0.062
(sin θ/λ)max (Å−1)0.596
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.070, 0.150, 1.12
No. of reflections1480
No. of parameters112
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)2.85, −3.62

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2000).

Selected geometric parameters (Å, º) top
Hg1—Br12.4234 (15)Hg1—N12.528 (13)
Br1—Hg1—Br1i153.72 (12)Br1i—Hg1—N1101.2 (3)
Br1—Hg1—N197.8 (3)N1—Hg1—N1i86.9 (6)
Symmetry code: (i) −x+2, y, −z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2A···O3ii0.821.752.56 (2)166
O3—H3A···O1iii0.84 (2)2.28 (3)2.89 (2)130 (2)
O3—H3B···N20.84 (2)2.09 (3)2.93 (2)177 (3)
Symmetry codes: (ii) −x+2, −y, −z+1; (iii) x−1/2, y−1/2, z.
 

Acknowledgements

The authors thank the Center for Testing and Analysis, Nanjing University for support.

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CSD CrossRef Web of Science Google Scholar
 First citationBruker (2000). SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationEnraf–Nonius (1989). CAD-4 Software. Version 5.0. Enraf–Nonius, Delft, The Netherlands.  Google Scholar
 First citationHarms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.  Google Scholar
 First citationNorth, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359.  CrossRef IUCr Journals Web of Science Google Scholar
 First citationO'Conner, C. J., Klein, C. L., Majeste, R. J. & Trefonas, L. M. (1982). Inorg. Chem. 21, 64–67.  Google Scholar
 First citationSheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.  Google Scholar
 First citationWang, X.-F., Lv, Y., Okamura, T., Kawaguchi, H., Wu, G., Sun, W.-Y. & Ueyama, N. (2007). Cryst. Growth Des. 7, 1125–1133.  Web of Science CSD CrossRef CAS Google Scholar
 First citationZhang, B.-S. (2005). Chin. J. Struct. Chem. 24, 478–482.  CAS Google Scholar
 First citationZou, J.-Z., Xu, Z., Chen, W., Lo, K. M. & You, X.-Z. (1999). Polyhedron, 18, 1507–1512.  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
Volume 64| Part 1| January 2008| Page m13
https://doi.org/10.1107/S1600536807061491
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS