Effect of Coulomb Exchange and Hybridization Effects on Magnetic Ordering in F-Electron Systems

A phenomenological study has been done to understand the unusual magnetic behaviors, especially the magnetic ordering based on the two-ion interaction between f electrons in correlated cerium systems. The nature of the two-ion interaction is studied from a free-electron band structure. Emphasis is put on investigating the effect of the two-ion interaction form on magnetic orderings. The study suggests an addition of some antiferromagnetic interaction into the two-ion interaction in order to achieve the essence of the experimental behaviors. It is demonstrated that a possible way of some antiferromagnetic interaction is from the spin polarization of the band structure. An explicit form of the two-ion interaction is provided that can satisfactorily describe the magnetic behaviors from the phenomenological point of view.