4-Benzylaminobiphenylglyoxime ligand and its Cu(II) and Co(II) complexes were prepared. BF2+-bridge containing 4-benzylaminobiphenylglyoxime complexes were obtained by replacing of the bridging protons of the dioxime complexes with BF2 group. These compounds have been characterized by elemental analysis, spectroscopic (ICP-OES, infra-red) and magnetic susceptibility measurements. Thermal decomposition of the complexes is studied in nitrogen atmosphere. The final decomposition products are found to be the corresponding metal oxides. The optical constants such as optical conductivity, dielectric constant, refractive index were determined for the complexes. The analysis of the optical absorption data revealed that the band gap E-g was direct transitions. The optical dispersion parameters were determined according to Wemple and Didomenico, method. (c) 2007 Elsevier B.V. All rights reserved.