Systematically improvable optimized atomic basis sets for {\it ab inito} calculations

TL;DR

This paper introduces a flexible, systematic method for constructing optimized atomic basis sets for density-functional calculations, improving accuracy and transferability through a wave function spillage minimization approach.

Contribution

The authors present a novel scheme for creating atomic basis sets that are fully optimized and systematically improvable, enhancing the accuracy of ab initio calculations.

Findings

Basis sets significantly reduce wave function spillage.

Systematic improvement enhances calculation accuracy.

Basis sets are highly transferable across systems.

Abstract

We propose a unique scheme to construct fully optimized atomic basis sets for density-functional calculations. The shapes of the radial functions are optimized by minimizing the {\it spillage} of the wave functions between the atomic orbital calculations and the converged plane wave calculations for dimer systems. The quality of the bases can be systematically improved by increasing the size of the bases within the same framework. The scheme is easy to implement and very flexible. We have done extensive tests of this scheme for wide variety of systems. The results show that the obtained atomic basis sets are very satisfactory for both accuracy and transferability.