Dielectric response in Ce-doped ThO2

We determine electronic and dielectric response of Cc doped and oxygen vacancy (O-vacancy) introduced thoria (ThO2), using first-principles density functional theory calculations based on pseudopotentials and a plane wave basis. We find significantly enhanced static dielectric response in ThO2 with Ce doping and introduction of oxygen vacancies. Softening and hardening of phonon modes and changes in the effective charges on atoms are found to be responsible for the dielectric response of doped samples compared to pure ThO2. (c) 2008 Elsevier B.V. All rights reserved.