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Updated: Jul 6, 2026
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Nonempirical statistical theory for molecular evaporation from nonrigid clusters
Mikiya Fujii1, Kazuo Takatsuka
1Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Tokyo, Japan. futofuji@mns2.c.u-tokyo.ac.jp
The Journal of Chemical Physics
|March 26, 2008
Summary
We developed a new statistical theory for molecular evaporation from clusters, accurately predicting reaction rates and fragment kinetic energy distributions. This method is validated by simulations of argon cluster evaporation.
Area of Science:
- Chemical Physics
- Theoretical Chemistry
- Statistical Mechanics
Background:
- Molecular clusters exhibit complex dynamics, including evaporation and isomerization.
- Predicting reaction rates and fragment energy distributions in nonrigid clusters is challenging.
Purpose of the Study:
- To develop a nonempirical statistical theory for molecular evaporation from nonrigid clusters.
- To accurately calculate reaction rates and kinetic energy distributions of fragments.
Main Methods:
- Devised an efficient method to evaluate classical density of states and flux at the dividing surface.
- Validated the theory using molecular dynamics simulations of Ar(2) evaporation from Ar(8).
Main Results:
- The nonempirical statistical theory accurately predicts reaction rates for molecular evaporation.
- The kinetic energy release (KER) of fragments follows a Boltzmann-like distribution.
- Established a general relation between KER and fragment temperature.
Conclusions:
- The proposed statistical theory provides an accurate and efficient approach for studying molecular evaporation.
- The findings offer insights into the relationship between kinetic energy release and temperature in cluster fragmentation.
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