Benchmarking Electronic-Structure Methods for the Description of Dark Transitions in Carbonyls at and Beyond the Franck-Condon Point.

ABSTRACT: Herein, we propose a comprehensive benchmark of electronic-structure methods to describe dark transitions, that is, transitions to excited electronic states characterized by a near-zero oscillator strength. This type of electronic state is particularly important for the photochemistry of molecules containing carbonyl groups, such as atmospheric volatile organic compounds (VOCs). The oscillator strength characterizing a dark transition can change dramatically by a slight alteration of the molecular geometry around its ground-state equilibrium, the so-called non-Condon effects. Hence, testing the performance of electronic-structure methods for dark transitions requires considering molecules at their Franck-Condon point (i.e., equilibrium geometry), but also beyond the Franck-Condon point. Ou

SUBMITTER: Bone J 

PROVIDER: S-EPMC12516729 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature