Studies on co-ordination complexes of silver(II). Part VI. Crystal and molecular structure of bis(pyridine-2,3-dicarboxylato)silver(II) dihydrate

Abstract

Crystals of bis(pyridine-2,3-dicarboxylato)silver(II) dihydrate are monoclinic, space group P2₁/n, with a= 6·002(4), b= 10·682(7), c= 12·842(8)Å, β= 90·83(10)°, and Z= 2. The intensities of 864 reflections above background were collected by counter methods and the structure has been refined to R 0·067. The structure consists of molecules of Ag (C₇H₄NO₄)₂ in which each ligand molecule is strongly bonded to the silver atom through the nitrogen atom [2·12(1)Å] and an oxygen atom of the carboxy-group in the 2-position [2·13(1)Å]. The stacking of the molecules in the a direction and the twist in the 3-carboxy-group leave the ketonic oxygen atoms O(4) in positions to form weak interactions (2·98 Å) with the silver atoms in adjacent (in a) molecules. Consequently the environment of each silver atom is best considered as approximating to a tetragonally distorted octahedron.