THERMAL, SPECTROSCOPIC AND MAGNETIC STUDIES OF SOME RARE-EARTH 3-HALOLAWSONEMONOXIMATES

The metal chelates of 3-chloro-, 3-bromo- and 3-iodo-derivatives of la wsonemonoxime with La(III), Sm(III) and Dy(III) have been synthesised. The thermal, spectral and magnetic properties of these chelates have been investigated to study the effect of variation of the C-3-halo-sub stituent on the chelating ability of the lawsonemonoxime. The energy o f activation E(a) and the order of reaction n for the decomposition st ages have been calculated using the Coats-Redfern relation.