Electronic couplings for singlet fission: Orbital choice and extrapolation to the complete basis set limit.

ABSTRACT: For the search for promising singlet fission candidates, the calculation of the effective electronic coupling, which is required to estimate the singlet fission rate between the initially excited state (S₀S₁) and the multiexcitonic state (¹TT, two triplets on neighboring molecules, coupled into a singlet), should be sufficiently reliable and fast enough to explore the configuration space. We propose here to modify the calculation of the effective electronic coupling using a nonorthogonal configuration interaction approach by: (a) using only one set of orbitals, optimized for the triplet state of the molecules, to describe all molecular electronic states, and (b) only taking the leading configurations into consideration. Furthermore, we also studied the basi

SUBMITTER: Speelman T 

PROVIDER: S-EPMC7898305 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature