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

TL;DR

This study investigates the pressure-induced transition of Li4rom metal to insulator using ab initio methods, revealing structural, electronic, and superconducting property changes under pressure.

Contribution

It provides a detailed ab initio analysis of phase transitions and electronic evolution in Li4ompounds under pressure, including anti-metallization mechanisms.

Findings

Phase transition from metal to insulator with increasing pressure

Quantitative description of anti-metallization via Fermi Surface Filling Ratio and band gap

Very weak electron-phonon coupling in metallic phases

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.