NON-KONDO PREDICTION OF WILSON RATIO FOR HEAVY-FERMION SYSTEMS

We propose a new two-electron band theory approach to treat correlated f-electron systems. This involves: first, an exact two-body treatment of the local correlations for a 'solid-state atom', i.e. non-spherica l local environment of a cerium (or other pertinent) nucleus; then, tu rning on the interactions giving extended two-electron states (bands). This approach treats the hybridization and exchange Coulomb interacti on effects within this two-body treatment on an equal footing. Without invoking the concept of Kondo resonance, it provides a non-magnetic s inglet state competing, side by side with other, magnetic states. It e xplains the wide diversity in f magnetism and the heavy fermion phenom enology, including the specific heat and susceptibility, and most sign ificant, provides an absolute prediction of the Wilson ratio, reproduc ing the experimental scale and trend in change of the Wilson (low-temp erature susceptibility to specific heat) ratio on going from non-magne tic to magnetic heavy fermion materials.