Valence fluctuation for f electrons in XGaO3 (X = Pu, Ce): a perspective from dynamic mean field theory

Abstract

A first principles calculation is performed on the electronic properties of XGaO3 (X = Pu, Ce) systems by combination of density functional theory with dynamical mean field theory. The results show that PuGaO3 has strong valance fluctuation, i.e., mixed-valent state, with an average occupancy of 5f electrons nf= 4.6695 as a consequence of mixture of 5f4 and 5f5 atomic configurations in the ground state. Similar work on CeGaO3 indicates that it is a semiconductor with a band gap of 2.7409 eV and with an average occupancy of 4f electrons nf = 1.0858. In contrast to PuGaO3, Ce 4f j = 5/2 and j = 7/2 states both exhibit insulating features.