Pressure-driven changes in the bonding energy of LaHx superhydrides.

Abstract

The nature of chemical bonding in lanthanum superhydrides (LaHx) was studied using Wannier-function-based energy decomposition together with Bader charge analysis. The evolution of ionic and covalent contributions, charge redistribution and pair-resolved bond energies were calculated using DFT as a function of volume (pressure). The approach demonstrated the fundamental difference between LaH3 and LaH10 and can be extended to other LaHx phases, revealing which atomic pairs (La-H, H-H, and La-La) govern the pressure-driven changes in bonding and stability.