The Thermal Decomposition of Metal Oxalato Complexes

The thermal decomposition of trioxalato complexes of cobalt(III), iron(III) and chromium-(III) has been investigated by the thermogravimetric, the polarographic and the infrared spectroscopic method. The results indicate that, in the case of the iron(III) and the cobalt(III) complexes, the decomposition reaction is initiated by the electron transfer from the coordinated oxalate ion to the central metal ion. In the case of oxalatoamminecobalt(III) complexes, the oxalate ion is considered to be an electron donor; the more oxalate ions are coordinated, the complexes are thermally less stable.