Identifying the ground state structures of point defects in solids

Abstract

Point defects are a universal feature of crystalline materials. Their identification is often addressed by combining experimental measurements with theoretical models. The standard approach of simulating defects is, however, prone to missing the ground state atomic configurations associated with energy-lowering reconstructions from the idealised crystallographic environment. Missed ground states compromise the accuracy of calculated properties. To address this issue, we report an approach to efficiently navigate the defect configurational landscape using targeted bond distortions and rattling. Application of our workflow to a range of materials ($\mathrm{CdTe}$, $\mathrm{GaAs}$, $\mathrm{S}{\mathrm{b}}_2{\mathrm{S}}_3$, $\mathrm{S}{\mathrm{b}}_2\mathrm{S}{\mathrm{e}}_3$, $\mathrm{Ce}{\mathrm{O}}_2$, $\mathrm{I}{\mathrm{n}}_2{\mathrm{O}}_3$, $\mathrm{ZnO}$, anatase-$\mathrm{Ti}{\mathrm{O}}_2$) reveals symmetry breaking in each host crystal that is not found via conventional local minimisation techniques. The point defect distortions are classified by the associated physico-chemical factors. We demonstrate the impact of these defect distortions on derived properties, including formation energies, concentrations and charge transition levels. Our work presents a step forward for quantitative modelling of imperfect solids.

References in corpus (19)

• High-pressure phases of silane
• Anion vacancies as a source of persistent photoconductivity in II-VI and chalcopyrite semiconductors
• Electrostatics-based finite-size correction for first-principles point defect calculations
• First-principles theory of nonradiative carrier capture via multiphonon emission
• Perovskite-Inspired Materials for Photovoltaics -- From Design to Devices
• Rapid Recombination by Cadmium Vacancies in CdTe
• DASP: Defect and Dopant ab-initio Simulation Package
• Lone pair driven anisotropy in antimony chalcogenide semiconductors
• Band Versus Polaron: Charge Transport in Antimony Chalcogenides
• Anharmonic Lattice Relaxation during Non-radiative Carrier Capture
• Hydrogen/silicon complexes in silicon from computational searches
• On the Dopability of Semiconductors and Governing Material Properties
• Impact of metastable defect structures on carrier recombination in solar cells
• Mass enhancement in 3d and s-p perovskites from symmetry breaking
• Hydrogen/nitrogen/oxygen defect complexes in silicon from computational searches
• Characterisation of negative-U defects in semiconductors
• An ab initio study of intrinsic defects in zirconolite
• Energetics of hydrogen/lithium complexes in silicon analyzed using the Maxwell construction
• Effect of local chemistry and structure on thermal transport in doped GaAs

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