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Good Vibrations: Calculating Excited-State Frequencies Using Ground-State Self-Consistent Field Models.

ABSTRACT: The use of Δ-self-consistent field (SCF) approaches for studying excited electronic states has received a renewed interest in recent years. In this work, the use of this scheme for calculating excited-state vibrational frequencies is examined. Results from Δ-SCF calculations for a set of representative molecules are compared with those obtained using configuration interaction with single substitutions (CIS) and time-dependent density functional theory (TD-DFT) methods. The use of an approximate spin purification model is also considered for cases where the excited-state SCF solution is spin-contaminated. The results of this work demonstrate that an SCF-based description of an excited-state potential energy surface can be an accurate and cost-effective alternative to CIS and TD-DFT methods.

SUBMITTER: Abou Taka A

PROVIDER: S-EPMC9753584 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Good Vibrations: Calculating Excited-State Frequencies Using Ground-State Self-Consistent Field Models.

Abou Taka Ali A Corzo Hector H HH Pribram Jones Aurora A Hratchian Hrant P HP

Journal of chemical theory and computation 20221129 12

The use of Δ-self-consistent field (SCF) approaches for studying excited electronic states has received a renewed interest in recent years. In this work, the use of this scheme for calculating excited-state vibrational frequencies is examined. Results from Δ-SCF calculations for a set of representative molecules are compared with those obtained using configuration interaction with single substitutions (CIS) and time-dependent density functional theory (TD-DFT) methods. The use of an approximate ...[more]

PMID: 36445860

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