Polarizability of molecular chains: does one need exact exchange?

TL;DR

This paper investigates the accuracy of different computational methods in predicting the static polarizability of long-chain polymers, highlighting the effectiveness of simple self-interaction corrected approximations as a cost-efficient alternative to exact exchange.

Contribution

It demonstrates that simple self-interaction corrected approximations outperform standard density functional methods and are comparable or better than exact exchange in predicting polarizability.

Findings

Standard density functionals overestimate polarizability

Exact exchange aligns well with Hartree-Fock results

Self-interaction corrected methods are computationally efficient and accurate

Abstract

Standard density functional approximations greatly over-estimate the static polarizability of longchain polymers, but Hartree-Fock or exact exchange calculations do not. Simple self-interaction corrected (SIC) approximations can be even better than exact exchange, while their computational cost can scale only linearly with the number of occupied orbitals.