Energy calculations of charged point defects on surfaces

TL;DR

This paper introduces a VIC method for calculating energies of charged point defects on surfaces, avoiding artificial charges and considering substrate effects, providing a more accurate energy estimation.

Contribution

The paper presents a novel VIC approach that accurately computes defect energies without artificial charges and accounts for substrate effects.

Findings

VIC method effectively models charged defects on surfaces.

Energy calculations align with Madelung energy approximations.

Method reduces artifacts from artificial charge introduction.

Abstract

We present a virtual ionic crystal (VIC) method to calculate energies of charged point defects on surfaces. No artificial charge but an actual zero-dimensional (0D) species is introduced to charge a defect. Effect of dielectric substrate on lattice energy is depressed through suitable configuration of the unit cell. The lattice energy approximates to Madelung energy with defect and 0D species considered as point charges in vacuum. Energy required to charge the defect is derived from charge quantity on the defect in VIC, energy of unit cell, and energy required to charge the 0D species.