Thermal, structural and electrical studies of the chloro complexes of cobalt, nickel and copper with 1,10-phenanthroline

Abstract

The chloro compounds of 1,10-phenanthroline with cobalt, nickel and copper have been prepared in ethanolic solution and have the stoichiometry ML nCl 2, where n = 2 for cobalt and copper and n = 1 for nickel. Solid compounds were isolated and characterised by analysis, magnetic moments, and vibrational and electronic spectra. The cobalt and copper compounds have octahedral structures, whereas the nickel compound has a tetrahedral structure. The thermal behaviour of the compounds has been studied using thermogravimetry and differential thermal analysis. During the thermal decomposition processes, intermediate compounds are produced. Electrical conductivity measurements were obtained for the 1,10-phenanthroline and its copper complex. No suitable discs could be obtained for electrical measurements on the cobalt and nickel complexes. The electrical measurements show ohmic behaviour at room temperature, with conductivities of 7.58 × 10 −8 Ω −1 m −1 for the 1,10-phenanthroline; and 9.10 × 10 −8Ω −1 m −1 for the copper complex.