Ab initio calculations on RE-TM-O3 perovskites: A comparative study of cation effect

The electronic and magnetic structures of orthorhombic perovskites RE-TM-O3 (RE = Eu, Gd, Tb and RE = Mn, Fe, Co) are studied using ab initio density functional theory in the local density approximation (LDA) with the on-site Hubbard Ueff parameter (LDA + U). To show rare earth (RE) and transition metal (TM) cations effect, we have analyzed the structural parameters, charge and spin densities and partial densities of states. We have also shown how the results can be made relatively sensitive to the choice of cation and to ion size. Valence electronic structures obtained from subsequent LDA + U calculations are compared and discussed.