Eur. Phys. J. B 68, 495-500 (2009)
https://doi.org/10.1140/epjb/e2009-00118-3

Direct overlapping effect of f orbitals for valence fluctuating materials in Kondo regime

¹ Département de Physique, Faculté des Sciences, Université de Toliara, 601 Toliara, Madagascar
² LPMR, Université d'Antananarivo, 101 Antananarivo, Madagascar
³ IPCMS, UMR 7504 CNRS, Université de Strasbourg, BP 43, 23 rue du Loess, 67034 Strasbourg, France

Corresponding author: ^a parlebas@ipcms.u-strasbg.fr

Received: 13 November 2008
Revised: 18 February 2009
Published online: 1 April 2009

Abstract

In Rare-Earth (RE) systems, direct overlapping of 4f orbitals plays a role if the distance between RE ions is sufficiently small. Especially, such a situation happens under pressure for RE metals and RE compounds. Furthermore, in Actinide systems, 5f orbitals are more extended than the previously considered 4f orbitals. Therefore, in this case, direct overlapping of 5f orbitals should be taken into account even without applying pressure. In the present work, using Standard Basis Operators, we study direct overlapping effect of f orbitals for valence fluctuating materials in Kondo regime. An important result within our present model is that direct f orbital overlapping reduces f electron effective mass.