Time-resolved photoelectron imaging spectra from non-adiabatic molecular dynamics simulations
Alexander Humeniuk1, Matthias Wohlgemuth, Toshinori Suzuki
1Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
The Journal of Chemical Physics
|October 15, 2013
Summary
We developed an efficient simulation method for time-resolved photoelectron imaging (TRPEI) spectra in molecules. This approach aids in interpreting photochemical processes and validating experimental data.
Area of Science:
- Computational chemistry
- Photochemistry
- Molecular dynamics
Background:
- Time-resolved photoelectron imaging (TRPEI) is crucial for studying ultrafast molecular dynamics.
- Simulating TRPEI spectra accurately for polyatomic molecules remains a challenge.
Purpose of the Study:
- To present an efficient computational method for simulating TRPEI spectra.
- To provide a tool for interpreting experimental TRPEI data and understanding photochemical processes.
Main Methods:
- Combines trajectory-based molecular dynamics with surface hopping for non-adiabatic effects.
- Employs an approximate photoionization treatment using Dyson orbitals and Coulomb waves.
- Implemented within the linear response time-dependent density functional theory framework.
Main Results:
- Successfully simulated time- and energy-resolved anisotropy maps for furan.
- Demonstrated good agreement with recent experimental data for furan.
- Validated the efficiency and applicability of the developed simulation method.
Conclusions:
- The presented method offers an efficient way to simulate TRPEI spectra.
- This computational approach can significantly aid in interpreting TRPEI experiments.
- It provides insights into fundamental photochemical processes in complex molecules.
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