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arXiv · 1506.06187

Crossover from Metal to Insulator in Dense Lithium-Rich Compound $\textrm{CLi}_{4}$

Xilian Jin·Xiao-Jia Chen·Huadi Zhang·Quan Zhuang·Kuo Bao·Dawei Zhou·Qiang Zhou·Zhi He·Bingbing Liu·Tian Cui
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Abstract

Crystal structures of $\textrm{CLi}_4$ compounds are explored through \emph{ab} \emph{initio} evolutionary methodology. Phase transition from metal to semimetal and semiconductor, and eventually to insulator with increasing pressure are revealed under pressure. Pressure-induced evolution of anti-metallization has been described quantitatively by Fermi Surface Filling Ratio and electron energy band gap using \emph{ab} \emph{initio} \emph{GW} calculations. Anti-metallization is attributed to the hybrid valence electrons and their repulsion by core electrons into the lattice interstices. Very weak electron-phonon coupling interactions are found in the metallic phases, resulting in very low superconducting temperature.

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Xilian Jin, Xiao-Jia Chen, Huadi Zhang, Quan Zhuang, Kuo Bao, Dawei Zhou, Qiang Zhou, Zhi He, Bingbing Liu, Tian Cui. 2016-01-11. Crossover from Metal to Insulator in Dense Lithium-Rich Compound $\textrm{CLi}_{4}$. https://doi.org/10.1073/pnas.1525412113

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