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Double Excitation Energies from Quantum Monte Carlo Using State-Specific Energy Optimization.

ABSTRACT: We show that recently developed quantum Monte Carlo methods, which provide accurate vertical transition energies for single excitations, also successfully treat double excitations. We study the double excitations in medium-sized molecules, some of which are challenging for high-level coupled-cluster calculations to model accurately. Our fixed-node diffusion Monte Carlo excitation energies are in very good agreement with reliable benchmarks, when available, and provide accurate predictions for excitation energies of difficult systems where reference values are lacking.

SUBMITTER: Shepard S

PROVIDER: S-EPMC9648196 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Double Excitation Energies from Quantum Monte Carlo Using State-Specific Energy Optimization.

Shepard Stuart S Panadés-Barrueta Ramón L RL Moroni Saverio S Scemama Anthony A Filippi Claudia C

Journal of chemical theory and computation 20221031 11

We show that recently developed quantum Monte Carlo methods, which provide accurate vertical transition energies for single excitations, also successfully treat double excitations. We study the double excitations in medium-sized molecules, some of which are challenging for high-level coupled-cluster calculations to model accurately. Our fixed-node diffusion Monte Carlo excitation energies are in very good agreement with reliable benchmarks, when available, and provide accurate predictions for ex ...[more]

PMID: 36314602

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