Synthesis, structures, and spectroscopic characterizations of the α and β forms of bis(N-phenmethyl-benzimidazole-N) dichloro cobalt(II) complex:: CoCl2(C7H5N2CH2Ph)2

Two modifications of the alpha and beta forms of bis(N-phenmethyl-benzimidazole-N)dichloro cobalt(II) complex, CoCl2(C7H5N2CH2Ph)(2), have been obtained by reacting N-phenmethyl-benzimidazole with CoCl2 in different reaction solvents. X-ray analysis reveals that the two modifications have a similar molecular structure with different geometric parameters. The alpha-form crystallizes in triclinic, P (1) over bar 1 space group and the beta form in the monoclinic, P2(1)/c space group. The crystal structures of both consist of monomeric molecules of [CoCl2(C7H5N2CH2Ph)(2)] with slightly distorted tetrahedron geometry for the CoCl2N2 chromophore. They are also characterized by elemental analysis, i.r. spectrum, electronic spectrum, and thermogravimetric differential thermal analysis.