(n,γ) reactions of metal complexes-III. Isothermal annealing of halide in 3-halo-2,4

The isothermal annealing behaviour of M(3-Xptdn)sub(n) is normal and constists of one step (M = Be2+, Cr(III), Fe(III), Co(III). Cu(II); X = Br, I). The plateau values of different transition metal complexes at a specific temperature (500-1000) are of the same order although their room temperature retention values are different. On the basis of the comparative study of the trends in activation energy and the trends in percentage retention at room temperature of the series of metal complexes a mechanism involving an exchange between the trapped Xsup(*) with 3C-X of coordinated ligand has been proposed for the isothermal annealing. (orig.)