Electronic and structural properties of rare earth metals at normal and high pressures: Eu and Yb

Ground state properties of the divalent rare earth metals Eu and Yb at ambient and high pressures are investigated by calculating their band structures and total energies using the linearized muffin-tin orbital method. To monitor the strengths of the 4f interactions in the local density approximation the hybridization of the 4f electrons is either fully included (itinerant model) or completely neglected (localized model). The effects of spin-polarization are also included for Eu. Divalent to trivalent valence transitions under pressure are discussed and compared with recent X-ray absorption experiments. For Yb, the structural stability of its fcc, bcc and hcp phases is investigated and results are presented.