Thermal decomposition of octahedral Ni(II) complexes with acetone 1-naphthoylhydrazone

Abstract

The thermal decompositions of acetone 1-naphthoylhydrazone (L) and its octahedral complexes with Ni(II), with the general formula NiL2X2 (X=Cl, Br, NO3 and NCS), were studied in air and nitrogen atmospheres. It was established that the organic ligand is decomposed in an exothermic processes, which is followed by oxidation of the decomposition fragments by atmospheric oxygen. At temperatures below 640°, all the complexes decompose completely, yielding NiO as the final product, which was confirmed by its X-ray analysis. From the difference between the enthalpy changes for the decompositions of the complexes and of the ligand itself, the nature of the final oxide, and the crystal field splitting parameters obtained from optical measurements, the corresponding stabilization energies were determined. © 1990 Wiley Heyden Ltd, Chichester and Akadémiai Kiadó, Budapest.