A Mixed Basis Approach for the Efficient Calculation of Potential Energy Surfaces

TL;DR

This paper introduces a mixed-basis set method combining pseudo-atomic orbitals and low-energy plane waves to efficiently and accurately calculate potential energy surfaces in density functional theory, reducing computational costs.

Contribution

The study presents a novel mixed-basis approach that improves computational efficiency for potential energy surface calculations in DFT without sacrificing accuracy.

Findings

Accurately calculates hydrogen dissociation barrier on Cu(111).

Reduces computational cost compared to traditional plane-wave methods.

Demonstrates effectiveness for molecule-surface interaction studies.

Abstract

First principles calculations based on density functional theory are having an incerasing impact on our understanding of molecule-surface interactions. For example, calculations of the multi-dimensional potential energy surface have provided considerable insight into th edynamics of dissociation processes. However, these calculations using a plane-wave basis set are very compute expensive if they are to be fully converged with respect to the plane-wave energy cutoff, k-point sampling, supercell size, slab thickness, etc. Because of this, in this study, we have implemented a mixed-basis set approach which uses pseudo-atomic orbitals and a few low-energy plane waves as the basis set within a density functional, pseudopotential calculation. We show that the method offers a computationally cheap but accurate alternative. The energy barrier for hydrogen dissociation on Cu(111) is calculated as an example.