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arXiv · 2402.08900

The photodissociation dynamics and ultrafast electron diffraction image of cyclobutanone from the surface hopping dynamics simulation

Abstract

The comprehension of nonadiabatic dynamics in polyatomic systems relies heavily on the simultaneous advancements in theoretical and experimental domains. The gas-phase electron diffraction (GUED) technique has attracted widespread attention as a promising tool for observing the photochemical and photophysical features at all-atomic level with high temporal and spatial resolutions. In this work, the GUED spectra were predicted to perform a double-blind test of accuracy in excited-state simulation for cyclobutanone based on the trajectory surface hopping method, with respect to the benchmark data obtained by upcoming MeV-GUED experiments at the Stanfold Linear Accelerator Laboratory. The results show that the ultrafast nonadiabatic dynamics occurs in the photoinduced dynamics, and two C2 and C3 channels play dominant roles in the nonadiabatic reactions of cyclobutanone. The simulated UED signal can be directly interpreted by atomic movements, providing a unique view to monitor the time-dependent evolution of the molecular structure in the femtosecond dynamics.

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Jiawei Peng, Hong Liu, Zhenggang Lan. 2024-02-14. The photodissociation dynamics and ultrafast electron diffraction image of cyclobutanone from the surface hopping dynamics simulation. https://arxiv.org/abs/2402.08900

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