抄録
D.C. electrical conductivity and Seebeck voltage of the synthesized solid solution x FeTiO3·(1−x)Fe2O3 of ilmenite (FeTiO3) and hematite (Fe2O3) were measured for a composition range of 1≥x≥0.33. It was found that both conductivity and Seebeck voltage change continuously with the composition. At room temperature, the conduction is that of p type for x>0.73 and n type for x<0.73. Judging from these results, it was concluded that the valence state of Ti ions in the compound is tetravalent for the whole range of composition. Conductivity of all specimens obeys a simple Wilson’s formula σ=σ0exp(−E⁄2kT) over a temperature range from 200°K to 970°K with two or three activation energies for each specimen. No anomalous change of conductivity could be observed at the ferrimagnetic or antiferromagnetic Curie point. It was, therefore, expected that the conduction electrons do not correlate with the magnetic spins in these compounds. Conductivity and Seebeck voltage of both ordered (ferrimagnetic) and disordered (antiferromagnetic) specimens with the same composition were compared. It was found that change of the ion arrangement does not affect electrical properties of these compounds.
