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Trajectory Surface Hopping Approach to Condensed-Phase Nonradiative Relaxation Dynamics Using Divide-and-Conquer
Hiroki Uratani1, Takeshi Yoshikawa2,3, Hiromi Nakai1,3,4
1Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan.
Journal of Chemical Theory and Computation
|February 12, 2021
Summary
This study introduces a new simulation method for molecular nonradiative relaxation in condensed phases. It reveals how solvent interactions significantly impact photoexcited molecule dynamics.
Area of Science:
- Photochemistry
- Computational Chemistry
- Molecular Dynamics
Background:
- Nonradiative relaxation of excited molecules is crucial in photochemistry.
- Environmental interactions, like solvents, significantly influence these dynamics in condensed phases.
Purpose of the Study:
- To develop an efficient non-adiabatic molecular dynamics simulation technique.
- To explicitly include environmental effects in nonradiative relaxation calculations without high computational cost.
Main Methods:
- Combined trajectory surface hopping with Tully's fewest-switches algorithm.
- Utilized a tight-binding approximated spin-flip time-dependent density-functional theory.
- Employed a divide-and-conquer (DC) spatial fragmentation scheme for large systems.
Main Results:
- The developed method efficiently simulates systems with thousands of atoms.
- Errors from DC fragmentation were found to be negligibly small.
- Provided molecular insights into the solvent dependence of trans-azobenzene photoexcited-state dynamics.
Conclusions:
- The new simulation technique accurately models condensed-phase nonradiative relaxation.
- Environmental effects are critical for understanding photoexcited-state dynamics in condensed phases.
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