Radiation decomposition of metal acetyl acetonates

Studies on the thermal decomposition of the acetyl acetonate complexes of transitional metal ions Cu/II/, Cr/III/, Mn/II/, Co/II/, Fe/III/, Vo/II/, Zn/II/, and Cd/II/ have been performed by thermogravimetric method. Taking the initial decomposition temperature as a measure of thermal stability, the relative order of the thermal stability of these complexes shows the following order: Zn/II/<Cd/II/< VO/II/<Fe/III/<Cr/III/<Cu/II/Co/II/< Mn/II/. The nature of decomposition of Cu/II/ and Cr/III/ complexes is similar, a sigmoid curve exists. In other cases a long linear decomposition follows the sigmoid pattern. The linear decomposition is a function of final decomposition temperature and percentage of decomposition. The kinetics of the decomposition is analyzed according to the Coats-Redfern equation. The results are discussed on the basis of structural and other aspects leading to the decomposition.