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Trajectory surface hopping in the time-dependent Kohn-Sham approach for electron-nuclear dynamics
Colleen F Craig1, Walter R Duncan, Oleg V Prezhdo
1Department of Chemistry, University of Washington, Seattle, 98195-1700, USA.
Physical Review Letters
|October 26, 2005
Summary
The trajectory surface-hopping time-dependent Kohn-Sham (TDKS) approach resolves issues in electron-nuclear interaction modeling. This method accurately simulates charge dynamics and relaxation in various systems, including biological molecules.
Area of Science:
- Computational Chemistry
- Quantum Mechanics
- Materials Science
Background:
- Mean-field approximations in time-dependent Kohn-Sham (TDKS) density functional theory lead to significant qualitative errors in describing electron-nuclear interactions.
- These inaccuracies manifest in phenomena such as current-induced heating in nanoelectronics, charge dynamics in quantum dots and carbon nanotubes, and the relaxation dynamics of biological chromophores.
Purpose of the Study:
- To address the limitations of the mean-field treatment in TDKS theory for electron-nuclear dynamics.
- To introduce and validate the trajectory surface-hopping TDKS approach as a robust alternative.
Main Methods:
- Implementation of the trajectory surface-hopping TDKS method.
- Application of the method to model photoinduced electron injection from a molecular chromophore into TiO2.
- Utilizing the approach to study the excited-state relaxation of the green fluorescent protein chromophore.
Main Results:
- The trajectory surface-hopping TDKS approach successfully resolves qualitative breakdowns observed in mean-field TDKS.
- Accurate simulation of complex charge dynamics and relaxation processes.
- Demonstrated efficacy in modeling photoinduced electron transfer and excited-state dynamics in relevant molecular systems.
Conclusions:
- The trajectory surface-hopping TDKS method provides a reliable framework for studying electron-nuclear dynamics.
- This approach overcomes critical limitations of standard TDKS, enabling more accurate predictions in nanoelectronics and photobiology.
- The validated method offers a pathway to better understanding and designing materials and molecular systems with specific optoelectronic or photochemical properties.
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