The performance of CIPSI on the ground state electronic energy of benzene

TL;DR

This paper evaluates the CIPSI method's accuracy in computing the ground state electronic energy of benzene, demonstrating its agreement with highly-accurate theoretical estimates.

Contribution

It provides an assessment of CIPSI's performance on benzene's correlation energy, extending previous work with a specific focus on this molecule.

Findings

CIPSI achieves a correlation energy of -863.4 mE_h for benzene.

The results agree with the theoretical estimate of -863 mE_h.

The study confirms CIPSI's effectiveness for molecular energy calculations.

Abstract

Following the recent work of Eriksen et al. [arXiv:2008.02678], we report the performance of the \textit{Configuration Interaction using a Perturbative Selection made Iteratively} (CIPSI) method on the non-relativistic frozen-core correlation energy of the benzene molecule in the cc-pVDZ basis. Following our usual protocol, we obtain a correlation energy of $-863.4$ m$E_h$ which agrees with the theoretical estimate of $-863$ m$E_h$ proposed by Eriksen et al. using an extensive array of highly-accurate new electronic structure methods.