Electronic Structure of Rare Earth-Doped Zirconia and Their Correlation to Oxygen Ion Diffusion

Abstract

We calculated the change in a chemical bonding state of rare earth-doped c-ZrO₂ during a diffusion process of oxygen ion using a first principle molecular orbital calculation. Bond overlap population (BOP), which corresponds to covalency, of Zr-O bond around moving oxygen ion is decreasing with a migration and have a minimum value at a saddle point. The migration enthalpy of oxygen ion in c-ZrO₂ is possibly related to the change in bonding state between a ground state and a transition state.