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Updated: Jul 11, 2026

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Theoretical studies of conjugation effects on excited state intramolecular hydrogen-atom transfer reactions in model
Carlos R Baiz1, Barry D Dunietz
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Abstract:
Intramolecular hydrogen-atom transfer dependence on electronic conjugation of curcumin and related molecular models in the ground state and 1pipi* excited state are computationally studied at the first-principles electronic structure level. The larger, more conjugated, systems exhibit a lower reaction barrier in the ground state but a higher barrier in the excited state. This is associated with a smaller increase in the conjugation upon excitation in the larger systems. Our studies provide a detailed description and analysis of these energy trends as well as an insight into the physical nature of the intramolecular hydrogen-atom transfer reactions.
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