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Kinetic prediction of reverse intersystem crossing in organic donor-acceptor molecules.

ABSTRACT: Reverse intersystem crossing (RISC), the uphill spin-flip process from a triplet to a singlet excited state, plays a key role in a wide range of photochemical applications. Understanding and predicting the kinetics of such processes in vastly different molecular structures would facilitate the rational material design. Here, we demonstrate a theoretical expression that successfully reproduces experimental RISC rate constants ranging over five orders of magnitude in twenty different molecules. We show that the spin flip occurs across the singlet-triplet crossing seam involving a higher-lying triplet excited state where the semi-classical Marcus parabola is no longer valid. The present model explains the counterintuitive substitution effects of bromine on the RISC rate constants of previously unknown molecules, providing a predictive tool for material design.

SUBMITTER: Aizawa N

PROVIDER: S-EPMC7411052 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Kinetic prediction of reverse intersystem crossing in organic donor-acceptor molecules.

Aizawa Naoya N Harabuchi Yu Y Maeda Satoshi S Pu Yong-Jin YJ

Nature communications 20200806 1

Reverse intersystem crossing (RISC), the uphill spin-flip process from a triplet to a singlet excited state, plays a key role in a wide range of photochemical applications. Understanding and predicting the kinetics of such processes in vastly different molecular structures would facilitate the rational material design. Here, we demonstrate a theoretical expression that successfully reproduces experimental RISC rate constants ranging over five orders of magnitude in twenty different molecules. We ...[more]

PMID: 32764588

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