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Equilibrium Structures of Propane and 2,2-Difluoropropane and Comparison with Other Two-Top Molecules
Jean Demaison1, Natalja Vogt2, Agnès Perrin3
1Physique des Lasers, Atomes et Molécules, Université de Lille, Bât. P5, CEDEX, 59655 Villeneuve d'Ascq, France.
Molecules (Basel, Switzerland)
|October 26, 2024
Summary
This study computed the equilibrium structures of propane and 2,2-difluoropropane using advanced computational methods. Comparisons with other molecules reveal insights into their chemical bonding through quantum theory.
Area of Science:
- Computational chemistry
- Quantum chemistry
- Molecular structure determination
Background:
- Accurate molecular structures are fundamental to understanding chemical properties and reactivity.
- Quantum chemical methods provide powerful tools for predicting and analyzing molecular geometries.
Purpose of the Study:
- To compute the ab initio equilibrium structures of propane and 2,2-difluoropropane.
- To determine the semiexperimental structure of propane.
- To compare the structures and discuss bonding using the quantum theory of atoms in molecules.
Main Methods:
- Coupled cluster with singles and doubles and perturbative triples (CCSD(T)) level of theory.
- Quadruple zeta quality basis set for ab initio calculations.
- MP2 level of theory for rovibrational corrections.
- Quantum theory of atoms in molecules (QTAIM) analysis.
Main Results:
- Calculated equilibrium structures for propane and 2,2-difluoropropane.
- Determined semiexperimental structure of propane.
- Provided structural comparisons and QTAIM-based discussion of bonding.
Conclusions:
- The study provides highly accurate structural data for propane and 2,2-difluoropropane.
- The findings contribute to a deeper understanding of chemical bonding in fluorinated alkanes.
- The methodology can be applied to study other molecular systems.
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