Validity of Anderson and Hubbard model for the description of Ce metal and cerium heavy fermion compounds
S. V. Streltsov, A. O. Shorikov, V. I. Anisimov
Institute of Metal Physics, Russian Academy of Sciences, 620041 Yekaterinburg GSP-170, Russia
Ural Federal University, Mira St. 19, 620002 Ekaterinburg, Russia
Abstract
The importance of taking into account inter-site f-f
hybridization in electron structure calculations for Ce metal and cerium
heavy fermion compounds was studied. We demonstrate that for heavy-fermion
systems such as cerium compound CeCu2Si2 f-f hybridization can be
neglected and Anderson model application is well justified. On another hand
for cerium metal f-f hybridization is strong enough to provide the
contribution to hybridization function comparable to hybridization between
4f and itinerant electrons. We argue that in the case of Ce only the most
general Hamiltonian combining Hubbard and Anderson models should be used.