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Conformational preference analysis in C2H6 using orbital forces and non-covalent interactions; comparison with
Trinidad Novoa1, Julia Contreras-García1, Patrick Chaquin1
1Laboratoire de Chimie Théorique (LCT) Sorbonne Université, CNRS, 4, Place Jussieu, F-75005, Paris, France. chaquin@lct.jussieu.fr.
Physical Chemistry Chemical Physics : PCCP
|January 23, 2023
Summary
Dynamic Orbital Forces and Non-Covalent Interactions reveal ethane
Area of Science:
- Computational Chemistry
- Molecular Interactions
- Quantum Chemistry
Background:
- Understanding molecular conformation is crucial in chemistry.
- Ethane's conformational preference has been a subject of study.
- Distinguishing between attractive and repulsive forces is key.
Purpose of the Study:
- To analyze attractive/repulsive interactions governing ethane's conformation.
- To investigate conformational preferences in related compounds.
- To decompose the rotation barrier into specific bond interactions.
Main Methods:
- Application of Dynamic Orbital Forces (DOF).
- Utilizing Non-Covalent Interactions (NCI) analysis.
- Examination of ethane and related compounds (e.g., CH3-SiH3, SiH3-SiH3, CH3-CF3, CF3-CF3).
Main Results:
- In ethane, attractive forces (2:1 ratio) dominate over repulsive forces for staggered vs. adiabatic eclipsed.
- Repulsive pi interactions primarily stabilize the staggered conformation vs. vertical eclipsed.
- Other compounds studied show predominantly repulsive interactions influencing conformation.
Conclusions:
- Ethane's staggered conformation is stabilized by a balance of attractive and repulsive forces.
- Hyperconjugation decreases in eclipsed conformations.
- Repulsive interactions are dominant in the conformational preferences of related silicon and fluorine compounds.
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