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We generalize the quasi-diabatic (QD) propagation scheme to simulate the non-adiabatic polariton dynamics in molecule–cavity hybrid systems. The adiabatic-Fock states, which are the tensor product states of the adiabatic electronic states of the molecule and photon Fock states, are used as the locally well-defined diabatic states for the dynamics propagation. These locally well-defined diabatic states allow using any diabatic quantum dynamics methods for dynamics propagation, and the definition of these states will be updated at every nuclear time step. We use several recently developed non-adiabatic mapping approaches as the diabatic dynamics methods to simulate polariton quantum dynamics in a Shin–Metiu model coupled to an optical cavity. The results obtained from the mapping approaches provide very accurate population dynamics compared to the numerically exact method and outperform the widely used mixed quantum-classical approaches, such as the Ehrenfest dynamics and the fewest switches surface hopping approach. We envision that the generalized QD scheme developed in this work will provide a powerful tool to perform the non-adiabatic polariton simulations by allowing a direct interface between the diabatic dynamics methods and ab initio polariton information.
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Inelastic Charge‐Transfer Dynamics in Donor–Bridge–Acceptor Systems Using Optimal Modes
A time‐convolutionless master equation approach for computing state‐to‐state rates was developed in which the coupling between states depends on the nuclear coordinates. This approach incorporates a fully quantum‐mechanical treatment of both the nuclear and electronic degrees of freedom and recovers the well‐known Marcus expression in the semiclassical limit. A significant breakthrough was made in using this approach by tying it to a fully ab initio quantum chemical approach for determining the diabatic states and electron‐phonon coupling terms, allowing unprecedented accuracy and utility for computing state‐to‐state electronic transition rates. The Weinstein group at the University of Sheffield reported recently upon a series of donor‐bridge‐acceptor (DBA) molecular triads whose electron‐transfer (ET) pathways can be radically changed by infrared light excitation of specific intramolecular vibrations. Once the diabatic states and couplings are determined, the TCLME approach is used to compute the time‐correlation functions and state‐to‐state golden‐rule rates.
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- PAR ID:
- 10061101
- Date Published:
- Journal Name:
- Advances in chemical physics
- ISSN:
- 0065-2385
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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