Electrical Transport Properties of Ca1 –xBixMnO3 – δ

Resumo

The electrical conductivity (σ) and thermoelectric power (S) of Ca_{1 –x}Bi_xMnO_{3 – δ} (х = 0.05, 0.10, 0.15) manganites with a perovskite-like structure have been measured in air in the temperature range 298–1223 K. Doping with bismuth increases the electron charge carrier concentration and leads to an increase in σ and S. The observed decrease in σ and S with increasing temperature is due to partial Mn³⁺ disproportionation into Mn²⁺ and Mn⁴⁺.