Crystal orbital overlap population based on all-electron ab initio simulation with numeric atom-centered orbitals and its application to chemical-bonding analysis in Li-intercalated layered materials

TL;DR

This paper introduces a new all-electron ab initio COOP analysis method using numeric atom-centered orbitals, applied to layered materials to understand chemical bonding and intercalation mechanisms relevant to batteries and superconductors.

Contribution

The study develops a novel COOP analysis code based on all-electron calculations with numeric atom-centered orbitals, enabling detailed chemical-bonding insights in layered materials.

Findings

COOP analysis reveals bonding changes during Li intercalation

Provides insights into stability and intercalation mechanisms

Demonstrates applicability to industrially relevant materials

Abstract

Crystal Orbital Overlap Population (COOP) is one of the effective tools for chemical-bonding analysis, and thus it has been utilized in the materials development and characterization. In this study, we developed a code to perform the COOP-based chemical-bonding analysis based on the wavefunction obtained from a first principles all-electron calculation with numeric atom-centered orbitals. The chemical-bonding analysis using the developed code was demonstrated for F2 and Si. Furthermore, we applied the method to analyze the chemical-bonding changes associated with a Li intercalation in three representative layered materials: graphite, MoS2, and ZrNCl, because of their great industrial importance, particularly for the applications in battery and superconducting materials. The COOP analysis provided some insights for understanding the intercalation mechanism and the stability of the intercalated materials from a chemical-bonding viewpoint.