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RADIOCHEMISTRY, STABLE ISOTOPES,
NUCLEAR ANALYTICAL METHODS, GENERAL CHEMISTRY
95
Fig.2. A molecular ribbon in the structure of Ca(4-IMC) 2 (H 2 O) viewed (a) along the b axis and (b) along the c axis.
lar ribbons are held together by a system of hydrogen
bonds.
X-ray diffraction data collection was carried out
on a KUMA KM4 four circle diffractometer at the
Institute of Nuclear Chemistry and Technology.
Structure solution and refinement was performed
using SHELXL programme package.
CRYSTAL CHEMISTRY OF COORDINATION COMPOUNDS
WITH HETEROCYCLIC CARBOXYLATE LIGANDS.
PART LVIII. THE CRYSTAL AND MOLECULAR STRUCTURE
OF A BARIUM(II) COMPLEX
WITH IMIDAZOLE-4,5-DICARBOXYLATE AND WATER LIGANDS
Wojciech Starosta, Janusz Leciejewicz, Thathan Premkumar 1/ , Subbian Govindarajan 1/
1/
Department of Chemistry, Bharathiar University, Coimbatore, Tamilnadu, India
The structure of poly-tetraaquabis(µ-Himidazole-4,5-dicarboxylato-N,O;-O’)
barium(II) dihydrate
(Ba(C 5
H 3
N 2
O 4
) 2
(H 2
O) 4·2H 2
O) is built of
molecular sheets in which singly deprotonated
imidazole-4,5-dicarboxylate ligand molecule
[H(4,5-IDA)] bridges metal ions using its N,O
ordinated by N,O bonding moieties of two ligand
molecules, two carboxylate oxygen atoms of two
another ligand molecules and four water oxygen
Fig.1. A fragment of the molecular sheet constituting the
structure of Ba[H(4,5-IDA)] 2
(H 2
O) 4·2H 2
O with atom
labelling scheme. Non-hydrogen atoms are drawn at
the 50% probability level.
bonding moiety and one oxygen atom of its second
carboxylate group. Each barium(II) ion is co-
Fig.2. A molecular layer in the structure of Ba[H(4,5-IDA)] 2
(H 2
O) 4·2H 2
O. For clarity, hydrogen atoms are not
shown.
atoms. The coordination number of a barium(II)
ion is ten, the coordination polyhedron contains
fourteen faces. Figure 1 shows a molecular unit of
the structure with atom labelling system, Fig.2 –