Effect of molecular and electronic geometries on the electronic density in FLO-SIC

TL;DR

This paper investigates how molecular and electronic geometries influence dipole moments and polarizabilities in non-cyclic molecules using FLO-SIC, emphasizing the importance of systematic parameter studies for consistent DFT and SIC results.

Contribution

It extends previous work by analyzing non-cyclic molecules and confirms the significance of systematic parameter studies in density functional theory and self-interaction correction.

Findings

DFT agrees well with experimental dipole moments.

SIC slightly overestimates dipole moments.

Linnett double-quartet geometry is energetically preferred for nitromethane.

Abstract

Recently, Trepte et al. [J. Chem. Phys., vol. 155, 2021] pointed out the importance of analyzing dipole moments in the Fermi-L\"owdin orbital (FLO) self-interaction correction (SIC) for cyclic, planar molecules. In this manuscript, the effect of the molecular and electronic geometries on dipole moments and polarizabilities is discussed for non-cyclic molecules. Computed values are presented for water, formaldehyde, and nitromethane. Continuing the work of Schwalbe et al. [J. Chem. Phys. vol. 153, (2020)], we reconfirm that systematic numerical parameter studies are essential to obtain consistent results in density functional theory (DFT) and SIC. In agreement with Trepte et al. [J. Chem. Phys., vol. 155, 2021], DFT agrees well with experiment for dipole moments, while SIC slightly overestimates them. A Linnett double-quartet electronic geometry is found to be energetically preferred for nitromethane.