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Updated: Oct 14, 2025
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
The configuration effect on the exciton dynamics of zinc chlorin aggregates
An Wei1, Siyuan Lv1, Yuan Zhang2
1Institute of Theoretical Physics, Department of Physics, University of Science and Technology, Beijing, Beijing 100083, China. luxiawang@sas.ustb.edu.cn.
Abstract:
Excitonic energy transfer among the zinc chlorin molecules is significant for the photovoltaic process because of their high sensitivities to harvesting sunlight. Zinc chlorin monomers and dimers can be synthesized experimentally, and they can form various self-assembled structures. Using the realistic parameters of zinc chlorin molecules, we assume that 20 molecules with J-, H- or J-H aggregation are arranged in a line and we investigate their dipole configuration effect on exciton dynamics. The expectation value approximation of operators is applied to derive the equations of motion of multi-exciton states. The temporal evolution of multi-exciton states is analyzed in the scheme of density matrix theory. Our simulations show that the inter-molecular coupling results in an exciton band and the wave-packet progressing excited by the resonant laser pulse exhibits attractive or repulsive behavior at the exciton level due to the dipole configuration effect. In the defined J-H coupling, the coherent wave-packet cannot overcome the configuration barrier to the no-excited part. The exciton dynamics revealed here might be helpful to better understand the energy transfer process in organic photovoltaic devices.
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