Shining X-Ray Light on the Volume Collapse Phenomenon of Cerium Metal

Elemental rare-earth metals exhibit intriguing properties arising from strong correlation effects due to partially filled f-electron shells. Of particular interest is the volume collapse phenomenon observed under high pressure conditions. In this study, we perform calculations including hybridization effects and atomic multiplet interactions to model recent high-pressure X-ray Raman measurements on Ce metals. We find that the X-ray measurement after the volume collapse is compatible with a Kondo screening scenario. However, direct 4f-4f hopping as in the Mott-Hubbard model also provides a small screening channel.