DEFECT STRUCTURE AND TRANSPORT-PROPERTIES OF MANGANESE OXIDE .1. THE NONSTOICHIOMETRY OF MANGANOSITE (MN-1-DELTA-O)

The deviation from stoichiometry DELTA in manganosite (Mn//1// minus // DELTA O) has been studied thermogravimetrically as a function of oxygen activity between 900 and 1400 degree C. Two formal fits of the deviation from stoichiometry as a function of oxygen activity and temperature are reported. From the experimental data, it is concluded that cation vacancies and holes are the predominant defect species over most or all of the manganosite stability range at high temperatures. The electrical conduction and cation diffusion in manganosite are analyzed briefly with regard to the defect structure of this oxide.