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arXiv · 1405.6934

Electronic structure and energetics of praseodymium and $\alpha$-plutonium under pressure

Nicola Lanatà·Yongxin Yao·Cai-Zhuang Wang·Kai-Ming Ho·Gabriel Kotliar
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Abstract

We develop a new implementation of the Gutzwiller approximation (GA) and interface it with the local density approximation (LDA). This formulation enables us to study complex $4f$ and $5f$ systems. We perform calculations of praseodymium and $\alpha$-plutonium under pressure, which compare very well with the experiments. Our study of praseodymium indicates that both structure change and $f$-delocalization are important to obtain the correct phase diagram and, in particular, the pressure-induced volume-collapse transition. Our calculations of $\alpha$-plutonium indicate that, even though the $f$ electrons are delocalized in this phase, the electron-correlations affect substantially its electronic structure and thermodynamical properties.

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Nicola Lanatà, Yongxin Yao, Cai-Zhuang Wang, Kai-Ming Ho, Gabriel Kotliar. 2014-05-27. Electronic structure and energetics of praseodymium and $\alpha$-plutonium under pressure. https://arxiv.org/abs/1405.6934

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