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arXiv · 1510.06798

Coherent dynamics of singlet fission controlled by nonlocal electron-phonon coupling

Yao Yao
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Abstract

Based on the Frenkel-charge transfer (CT) mixing model of singlet fission (SF), we incorporate both the local and nonlocal phonon baths in the Hamiltonian and adopt the algorithm of time-dependent density matrix renormalization group to simulate the fission process in tetracene. The endergonic SF is found to be facilitated by the robust quantum coherence, which concurrently gives rise to a notable quantum beating effect. Controlled by the nonlocal electron-phonon coupling, the density of triplet yield manifests a nonlinear relationship with the singlet density. As a result, the fission rate in tetracene is explicitly obtained, which is in agreement with the experimental measurement.

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Yao Yao. 2015-10-28. Coherent dynamics of singlet fission controlled by nonlocal electron-phonon coupling. https://doi.org/10.1103/physrevb.93.115426

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