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Updated: May 20, 2026
06:37
Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
Long-timescale simulations of diffusion in molecular solids
L J Karssemeijer1, A Pedersen, H Jónsson
1Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Physical Chemistry Chemical Physics : PCCP
|July 12, 2012
Summary
Adaptive kinetic Monte Carlo simulations reveal CO diffusion on water ice, crucial for interstellar organic compound formation. This method efficiently models molecular solids, even at low temperatures.
Area of Science:
- Physical Chemistry
- Computational Materials Science
- Astrochemistry
Background:
- Kinetic processes are fundamental to molecular layer formation and evolution.
- Simulating these processes is key to understanding molecular solids and their roles in various environments.
Purpose of the Study:
- To highlight adaptive kinetic Monte Carlo as a powerful simulation technique for molecular solids.
- To demonstrate its application in modeling CO diffusion on water ice surfaces.
Main Methods:
- Adaptive kinetic Monte Carlo simulations.
- Coarse-graining algorithm for enhanced efficiency at low temperatures (down to 10 K).
- On- and off-lattice kinetic Monte Carlo techniques.
Main Results:
- Simulated CO diffusion on water ice follows Arrhenius behavior.
- Effective activation energy for CO diffusion determined as 50 ± 1 meV.
- Coarse-graining significantly improves simulation efficiency without altering physical processes.
Conclusions:
- Adaptive kinetic Monte Carlo is effective for studying kinetic processes in molecular solids.
- CO diffusion on water ice is a key process for interstellar organic compound formation.
- Combining on- and off-lattice methods enables large-scale, long-term simulations of molecular solids.
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