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Published on: March 24, 2018
Interactions between anionic and neutral bromine and rare gas atoms
Alexei A Buchachenko1, Timur A Grinev, Timothy G Wright
1Department of Chemistry, Moscow State University, Moscow 119991, Russia. alexei@classic.chem.msu.su
The Journal of Chemical Physics
|February 20, 2008
Summary
High-quality potential energy functions for bromine interactions with rare gases were computed. These accurate theoretical potentials precisely predict experimental data for bromine atoms and anions.
Area of Science:
- Chemical Physics
- Quantum Chemistry
- Atomic and Molecular Interactions
Background:
- Accurate potential energy functions are crucial for understanding atomic and molecular interactions.
- Previous studies have provided insights into bromine-rare gas interactions, but refinements are needed.
Purpose of the Study:
- To compute high-quality, ab initio potential energy functions for bromine atoms and anions interacting with rare gases (He to Rn).
- To refine existing potentials and investigate the influence of spin-orbit coupling.
Main Methods:
- Utilized the coupled cluster method with single and double excitations and noniterative correction to triple excitations [RCCSD(T)] extrapolated to the complete basis set limit.
- Employed spin-restricted and relativistic approaches, including spin-orbit coupling calculations.
- Calculated potentials for nonrelativistic (2)Sigma(+) and (2)Pi electronic states.
Main Results:
- Obtained highly accurate potential energy functions for Br-Rg and Br(-)-Rg systems.
- Spin-orbit coupling significantly affected Br-Xe and Br-Rn interactions.
- Calculated photoelectron spectra, scattering cross sections, and transport coefficients showed excellent agreement with experimental data.
Conclusions:
- The developed ab initio potentials demonstrate very high precision for bromine-rare gas interactions.
- These potentials are valuable for accurate theoretical predictions and understanding chemical dynamics.
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