Multipole interactions of Γ3 non-Kramers doublet systems on cubic lattices

Abstract

We investigate the multipole interactions between adjacent f2 ions with the Γ3 crystalline electric field (CEF) ground state. In this study, we consider only the Γ8 states as the one-electron states. We construct the Γ3 doublet state of the electrons in the Γ8 states, and indeed, it can become the CEF ground state of a simple model Hamiltonian. To derive the multipole interactions, we apply the second-order perturbation theory with respect to the intersite hopping. We obtain no multipole interaction for a simple cubic lattice and octupole interactions for bcc and fcc lattices. We discuss the similarities and differences in the multipole interactions among the models with the local Γ3 CEF states.