The Radiolysis of Crystalline Oxalato Metal Complexes. The Effects of Coordinating Metal Ions on the Radiolysis of Oxalate

Abstract

Coordinated oxalates in metal complexes are more reactive under γ-irradiation than are ionic oxalates. This suggests that the covalency between the metal ion and the ligand in oxalato metal complexes promotes the reactivity of the ligand. The reaction of the ligand is also affected by the central metal ions. In K3[Co(C2O4)3]·3H2O and K3[Fe(C2O4)3]·3H2O, the coupled reduction of central metal ions with the oxidative decomposition of the ligand to carbon dioxide occurs at relatively high G values. In K3[Cr(C2O4)3]·3H2O, the redox reaction of the central metal ion is small and the ligand decomposes into carbon dioxide and carbon monoxide. In K3[Al(C2O4)3]·H2O, the formation of glyoxal and formic acid instead of carbon monoxide is significant.