Pseudopotential density functional treament of atoms and molecules in cartesian coordinate grid

TL;DR

This paper extends pseudopotential density functional theory calculations for atoms and molecules on a Cartesian grid, demonstrating broad applicability and improved accuracy with specific exchange-correlation functionals, validated against literature and experimental data.

Contribution

It introduces an enhanced DFT pseudopotential approach on a Cartesian grid applicable to a wide range of species and functionals, with improved HOMO energy predictions.

Findings

Excellent agreement with literature data on energies and eigenvalues

Significant improvement in HOMO energies using Leeuwen-Baerends exchange potential

Validated results against experimental data where available

Abstract

This is a follow-up of our recently proposed work on pseudopotential calculation (Ref. [21]) of atoms and molecules within DFT framework, using cartesian coordinate grid. Detailed results are presented to demonstrate the usefulness, applicability of the same for a larger set of species (5 atoms; 53 molecules) and exchange-correlation functionals (local, nonlocal). A thorough comparison on total, component, ionization, atomization energies, eigenvalues, potential energy curves with available literature data shows excellent agreement. Additionally, HOMO energies for a series of molecules show significant improvements by using the Leeuwen-Baerends exchange potential, compared to other functionals considered. Comparison with experiments has been made, wherever possible.