Static disorder and structural correlations in the low temperature phase of lithium imide

TL;DR

This study uses ab-initio molecular dynamics to clarify the low temperature crystal structure of lithium imide, revealing site occupation correlations that align with experimental data and resolve previous structural ambiguities.

Contribution

The paper provides a detailed atomic-level understanding of lithium imide's low temperature phase, highlighting the role of site occupation correlations through advanced simulations.

Findings

Correlation in Li site occupation explains experimental diffraction data

Simulation results resolve previous structural inconsistencies

Atomic positions match well with experimental observations

Abstract

Based on ab-initio molecular dynamics simulations, we investigate the low temperature crystal structure of Li2NH which in spite of its great interest as H-storage material is still matter of debate. The dynamical simulations reveal a precise correlation in the fractional occupation of Li sites which leads average atomic positions in excellent agreement with diffraction data and solves inconsistencies of previous proposals.