The thermolysis of some transition metal ferrioxalate precursors, M-3[Fe(ox
)(3)](2). xH(2)O (M = Mn, Co, Ni, Cu) has been studied in a static air atmo
sphere from ambient to 600 degreesC. Various physicochemical techniques e.g
. TG, DTG, DTA, XRD, IR, Mossbauer etc. have been employed to characterize
the intermediates and products. After dehydration the anhydrous precursors
undergo decomposition to yield an iron(II) intermediate, M[Fe-II(ox)(2)] (M
= Mn, Co, Ni) in the temperature range 175-290 degreesC. A subsequent oxid
ative decomposition of the iron(II) species leads to the formation of alpha
-Fe2O3 and MO in successive stages. Finally a solid state reaction occurs
between the oxides above 400 degreesC resulting in the formation of transit
ion metal ferrites, MFe2O4. The ferrites have been obtained at much lower t
emperature and in less time than in the conventional ceramic method.