Static dipole polarizabilities of polyacenes using self-interaction-corrected density functional approximations

TL;DR

This study evaluates the effectiveness of self-interaction correction methods in density functional theory for accurately predicting the polarizabilities and ionization potentials of polyacenes, showing LSIC's superior performance.

Contribution

It introduces and tests the locally-scaled self-interaction correction (LSIC) method, demonstrating its improved accuracy over FLOSIC-DFA for polyacenes.

Findings

LSIC removes overcorrection tendency of FLOSIC-DFA.

LSIC results align closely with CCSD reference values.

Vertical ionization potentials agree well with experiments.

Abstract

Density functional approximations are known to significantly overestimate the polarizabilities of long chain-like molecules. We study the static electric dipole polarizabilities and the vertical ionization potentials of polyacenes from benzene to pentacene using the Fermi-L\"owdin orbital based self-interaction corrected (FLOSIC) density functional method. The orbital-by-orbital self-interaction correction corrects for the overestimation tendency of density functional approximations. The polarizabilities calculated with FLOSIC-DFA are however overly corrected. We also tested the recently developed locally-scaled self-interaction correction (LSIC) method on the polyacenes. The local-scaling method applies full SIC in the one-electron regions and restores the proper behavior of the SIC exchange-correlation functionals in the uniform density limit. The results show that LSIC removes the overcorrection tendency of the FLOSIC-DFA and produces results that are in excellent agreement with reference CCSD values. The vertical ionization potentials with LSIC also show good agreement with available experimental values.