Workhorse minimally-empirical dispersion-corrected density functional, with tests for weakly-bound systems: r$^{2}$SCAN+rVV10

TL;DR

This paper refines the r$^{2}$SCAN+rVV10 density functional to enhance accuracy and stability, demonstrating superior performance in predicting molecular interactions, layered material properties, and interlayer binding energies compared to previous methods.

Contribution

The paper introduces a refitted r$^{2}$SCAN+rVV10 functional with improved numerical stability and accuracy for weakly-bound systems and layered materials.

Findings

Outperforms SCAN+rVV10 in efficiency and accuracy

Accurately predicts lattice constants and interlayer binding energies

Provides excellent phonon dispersion results

Abstract

SCAN+rVV10 has been demonstrated to be a versatile van der Waals (vdW) density functional that delivers good predictions of both energetic and structural properties for many types of bonding. Recently, the r$^{2}$SCAN functional has been devised as a revised form of SCAN with improved numerical stability. In this work, we refit the rVV10 functional to optimize the r$^{2}$SCAN+rVV10 vdW density functional, and test its performance for molecular interactions and layered materials. Our molecular tests demonstrate that r$^{2}$SCAN+rVV10 outperforms its predecessor SCAN+rVV10 in both efficiency (numerical stability) and accuracy. This good performance is also found in lattice constant predictions. In comparison with benchmark results from higher-level theories or experiments, r$^{2}$SCAN+rVV10 yields excellent interlayer binding energies and phonon dispersions for layered materials.