Effect of finite f level linewidth on the theory of the x-y transition in Ce.

Abstract

We have extended the Ramirez-Falicov theory of the a-y transition in Ce to include the effect of hybridization of the localized 4f states with the band. The physical properties of the x and y phases are calculated using thermodynamic Green functions which are determined by a decoupling procedure that accounts for the highly correlated character of the f levels. The decoupling procedure is exact to second order in the hybridization parameter. We find satisfactory valúes for the noninteger valency, electronic specific heat and magnetic susceptibility of the a phase. A Curie law for the y phase is also obtained.