The effect of charge fluctuation and transfer on the exchange interaction in rare-earth and actinide systems - Liang-Jian, Z.; Qing-Qi, Z. (Elsevier)
Starting with the Anderson lattice model, an extended effective exchange interaction is derived by the Schrieffer-Wolff transformation. The effective Hamiltonian includes not only the usual s-f exchange term but also a second order interaction term due to the charge transfer effect. Within the Hartree-Fock approximation, the indirect exchange interaction between f-electrons includes both the terms depending on the number of f-electron and the traditional RKKY interaction. Numerical calculation of the effective exchange interaction is performed and discussed. Making use of the derived Hamiltonian, the magnetic susceptibilities of two typical heavy-fermion materials are studied.
http://linkinghub.elsevier.com/retrieve/pii/0304-8853(92)91755-I
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