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arXiv · 1504.04551

Electronic Origin of the Volume Collapse in Cerium

N. Devaux·M. Casula·F. Decremps·S. Sorella
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Abstract

The cerium alpha-gamma phase transition is characterized by means of a many-body Jastrow-correlated wave function, which minimizes the variational energy of the first-principles scalar-relativistic Hamiltonian, and includes correlation effects in a non-perturbative way. Our variational ansatz accurately reproduces the structural properties of the two phases, and proves that even at temperature $T=0$K the system undergoes a first order transition, with ab initio parameters which are seamlessly connected to the ones measured by experiment at finite $T$. We show that the transition is related to a complex rearrangement of the electronic structure, with key role played by the p-f hybridization. The underlying mechanism unveiled by this work can hold in many Ce-bearing compounds, and more generally in other f-electron systems.

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N. Devaux, M. Casula, F. Decremps, S. Sorella. 2015-04-17. Electronic Origin of the Volume Collapse in Cerium. https://doi.org/10.1103/physrevb.91.081101

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