An excitation matched local correlation approach to excited state specific perturbation theory

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Clune, Rachel, Neuscamman, Eric
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866909609092972544
author Clune, Rachel
Neuscamman, Eric
author_facet Clune, Rachel
Neuscamman, Eric
contents We develop a cubic scaling approach to excited-state-specific second order perturbation theory in which the completeness of a local correlation treatment is carefully matched between the ground and excited state. With this matching, the accuracy of the parent method is maintained even as substantial portions of the correlation energy are neglected. Even when treating a long-range charge transfer excitation, cubic scaling is achieved in systems with as few as ten non-hydrogen atoms. In a test on the influence of an explicit solvent molecule on a long range charge transfer, the approach is qualitatively more accurate than EOM-CCSD and reproduces CC3's excitation energies and excited state potential energy surface to within about 0.1 eV and 0.5 kcal/mol, respectively.
format Preprint
id arxiv_https___arxiv_org_abs_2505_08659
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle An excitation matched local correlation approach to excited state specific perturbation theory
Clune, Rachel
Neuscamman, Eric
Chemical Physics
We develop a cubic scaling approach to excited-state-specific second order perturbation theory in which the completeness of a local correlation treatment is carefully matched between the ground and excited state. With this matching, the accuracy of the parent method is maintained even as substantial portions of the correlation energy are neglected. Even when treating a long-range charge transfer excitation, cubic scaling is achieved in systems with as few as ten non-hydrogen atoms. In a test on the influence of an explicit solvent molecule on a long range charge transfer, the approach is qualitatively more accurate than EOM-CCSD and reproduces CC3's excitation energies and excited state potential energy surface to within about 0.1 eV and 0.5 kcal/mol, respectively.
title An excitation matched local correlation approach to excited state specific perturbation theory
topic Chemical Physics
url https://arxiv.org/abs/2505.08659