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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Kinematic effects associated with molecular frames in structural isomerization dynamics of clusters.
Tomohiro Yanao1, Kazuo Takatsuka
1Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Komaba, 153-8902, Tokyo, Japan. yanao@mns2.c.u-tokyo.ac.jp
The Journal of Chemical Physics
|July 23, 2004
Summary
Investigating molecular frame movements in triatomic clusters reveals a "democratic centrifugal force" that traps systems near transition states. A newly examined gauge field significantly suppresses isomerization reaction rates, challenging existing theories.
Area of Science:
- Chemical Physics
- Molecular Dynamics
- Quantum Chemistry
Background:
- Structural isomerization dynamics in molecular clusters are crucial for understanding chemical reactions.
- Conventional reaction rate theories often overlook kinematic effects and gauge fields in internal molecular spaces.
Purpose of the Study:
- To investigate kinematic effects on structural isomerization dynamics in zero total angular momentum triatomic clusters.
- To analyze the influence of a gauge field associated with the Eckart frame on isomerization reaction rates.
Main Methods:
- Employed principal-axis hyperspherical coordinates for systematic analysis of isomerization dynamics.
- Extracted a
- democratic centrifugal force
- arising from the internal space's non-Euclidean metric.
- Performed numerical comparisons of dynamics with and without the gauge field.
Main Results:
- Identified a
- democratic centrifugal force
- that distorts clusters and creates basins at transition states.
- Demonstrated that the gauge field associated with the Eckart frame significantly suppresses isomerization reaction rates.
- Revealed the physical origin of this rate-suppressing effect.
Conclusions:
- Kinematic effects, including the democratic centrifugal force and the gauge field, play a critical role in molecular isomerization dynamics.
- Neglecting these kinematic effects leads to significant overestimation of isomerization reaction rates.
- The study provides a more accurate theoretical framework for understanding molecular reaction dynamics.
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