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Updated: Jan 14, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
9.0K
A Density Functional Theory and Semiempirical Framework for Trajectory Surface Hopping on Extended Systems
Jan-Robert Vogt1, Michael Schulz1, Rafael Souza Mattos2
1Christian-Albrechts-University Kiel, Max-Eyth-Strasse 1, 24118 Kiel, Germany.
Journal of Chemical Theory and Computation
|October 18, 2025
Summary
We developed an interface for nonadiabatic molecular dynamics simulations in solids. This tool enhances theoretical understanding of excited-state processes in photochemistry, enabling efficient computation of broad spectra.
Area of Science:
- Computational Chemistry
- Photochemistry
- Solid-State Physics
Background:
- Nonadiabatic molecular dynamics (NAMD) simulations are crucial for understanding excited-state processes in photochemistry.
- Existing theoretical methods, particularly within time-dependent density functional theory (TD-DFT), are limited for systems with periodic boundary conditions.
- There is a need for robust computational tools to bridge the gap between molecular and solid-state NAMD.
Purpose of the Study:
- To present a novel interface connecting the CP2K electronic structure code with the NEWTON-X surface hopping code.
- To enable efficient NAMD simulations for solid-state systems, complementing existing software.
- To provide a reliable method for calculating excited-state properties, including spectra and dynamics.
Main Methods:
- Developed an interface between CP2K and NEWTON-X for NAMD simulations.
- Implemented methods for generating initial conditions and performing adiabatic/nonadiabatic dynamics.
- Utilized phenomenological or numerical time-derivative couplings for surface hopping.
- Validated setups using gas-phase and crystalline pyrazine systems.
- Employed a mixed semiempirical density functional theory (DFT) approach for computational efficiency.
Main Results:
- The interface accurately reproduces electronic absorption spectra and excited-state populations for gas-phase pyrazine, aligning with established methods.
- Demonstrated the ability to compute broad spectra (several eV) and simulate 100 fs trajectories for crystalline pyrazine.
- Successfully considered couplings among the 80 lowest excited states.
- Showcased the efficiency and applicability of the interface for larger, periodic systems at low computational cost.
Conclusions:
- The developed interface effectively bridges the gap for solid-state NAMD simulations.
- The tool provides accurate theoretical insights into photochemical excited-state processes in periodic systems.
- This work offers a computationally efficient and applicable method for studying complex excited-state phenomena in materials.
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