Conduction mechanism in transition-metal oxides

Electrical conduction in 3d transition-metal oxide compounds (e.g., Sc-doped SrTiO3) with oxygen vacancy is studied from the theoretical viewpoint. A conduction mechanism due to the motion of proton tunneling and hopping in the double minimum potential between two oxygen ions is proposed in the hole-doped perovskite structure with Ti-site substitution by Sc. Furthermore, 3d-2p electronic properties in the proton conducting Ti-oxides are discussed in comparison with those in high-T-c superconducting Cu-oxides.