Theoretical study of local electronic transitions in the NiO(100) surface

Abstract

Local transitions at the NiO(100) surface have been studied with ab initio calculations by means of CASSCF/CASPT2. In addition to the well-known surface specific d–d transition at 0.6 eV, also the recently proposed surface d–d transition at 2.1 eV is confirmed. The broad peak at 1 eV is proposed to consist of transitions to the surface 3B 2, 3A 2, and b 3E d 8 states and the bulk 3T 2g state. Furthermore, the relative energies of the local ligand to metal charge transfer excitations have been investigated. The lowest local CT state in NiO(100) has been calculated to be about 2 eV lower than in bulk NiO.