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Thermogravimetric analysis of solid state bis-Cu(II) amine complexes CuL2X2, where X-CI or NO~ and L = ethylenediamina (en), tetramethylethylenediamine (tmn), ophenylenediamine (opd) and 2,2' bipyridyt (bpy), has been Carried out and the kinetic parameters have been determined by fitting the observed mass losses corresponding to various steps using the Coats and Redfern equation. These studies show that the activation energies of these complexes decrease on changing the ligand in the order: bpy >opd > en > tmn. This trend can be attributed to the rigidity of the N~--N skeleton in the bpy and opd ligands and steric crowding at the nitrogens in the tmn ligand. The majority of the decomposition steps were found to be composite in nature and frequently involved fractional groups expelled from the complexes. From the observation of E, > A H, the thermal decomposition process of these complexes appears to be governed by the "nucleation and growth" mechanism.Our studies on the temperature dependence of the electrical conductivity of some solid state bis Cu(II) amine complexes CuLzX 2 where X = CI-or N~) 3 and L = ethylenediamine (en), tetramethylethylenediamine (tmn), o-phenylenediamine (opd) and 2,2' bipyridyl (bpy), exhibited a number of discontinuities in various temperature intervals which are indicative of structural phase changes and/or thermal decomposition. Though the literature on such coordination complexes is quite extensive [1], except for some complexes of Cu(II)SO4 [2], very little is known about their thermal stability. Therefore, in order to understand the reasons for the above-mentioned-discontinuities in the electrical conductivity at various temperatures, the thermal properties of the complexes were studied. ExperimentalThe above-mentioned Cu(II) amine complexes were prepared by treating aqueous alcoholic solutions of CuX 2 (X = C1-or NO~) and the appropriate ligands L (en, tmn, opd, bpy) in the stoichiometric ratio of 1:2 by following procedures similar to those reported in the literature [3]. The complexes were characterised by elemental microanalysis (C, H, N