Theoretical Study of Lithium Ionic Conductors by Electronic Stress Tensor Density and Electronic Kinetic Energy Density

TL;DR

This study uses electronic stress tensor and kinetic energy density analyses to differentiate ionic bonds from metalloid bonds in lithium conductors, revealing that bond morphology provides key distinctions.

Contribution

It introduces a novel approach using electronic stress tensor and kinetic energy density to analyze and distinguish bonding types in lithium ionic conductors.

Findings

Eigenvalue patterns do not distinguish bond types.

Bond morphology of the electronic interface differentiates ionic from metalloid bonds.

Electronic kinetic energy density zero surface is a key indicator.

Abstract

We analyze the electronic structure of lithium ionic conductors, ${\rm Li_3PO_4}$ and ${\rm Li_3PS_4}$, using the electronic stress tensor density and kinetic energy density with special focus on the ionic bonds among them. We find that, as long as we examine the pattern of the eigenvalues of the electronic stress tensor density, we cannot distinguish between the ionic bonds and bonds among metalloid atoms. We then show that they can be distinguished by looking at the morphology of the electronic interface, the zero surface of the electronic kinetic energy density.