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Updated: Jul 2, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Structure, conformation and NMR studies on 1,2-dioxane and halogen substituted 1,2-dioxane molecules
K Senthilkumar1, P Kolandaivel
1Department of Physics, Bharathiar University, Coimbatore 641 046, India. ponkvel@hotmail.com
Computational Biology and Chemistry
|August 21, 2003
Summary
This study investigates the molecular structure and stability of 1,2-dioxane and its halogenated derivatives using computational methods. DFT calculations reveal key insights into conformational preferences and electronic interactions, aiding in understanding these cyclic ethers.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Organic Chemistry
Background:
- 1,2-Dioxane and its derivatives are important cyclic ethers with diverse applications.
- Understanding their molecular structure and conformational stability is crucial for predicting their chemical behavior.
Purpose of the Study:
- To investigate the molecular structure and conformational stability of 1,2-dioxane and its halogen-substituted compounds.
- To analyze the influence of halogen substitution on the chair and twist conformers.
- To explore the effect of polar solvents on the conformational landscape.
Main Methods:
- Ab initio and Density Functional Theory (DFT) methods were employed.
- Molecular geometries were optimized using various levels of theory (HF, MP2, B3LYP, B3PW91) with a 6-31G* basis set.
- Self-consistent reaction field theory was used to model polar solvent effects.
Main Results:
- Geometrical parameters of chair and twist conformers were analyzed, considering lone pair-halogen interactions.
- Relative stability of conformers was assessed through relative energy, maximum hardness principle, and thermodynamic quantities.
- 13C-NMR chemical shifts were calculated and discussed for the studied compounds.
Conclusions:
- Computational methods provide valuable insights into the structural and electronic properties of 1,2-dioxane derivatives.
- Halogen substitution significantly influences the conformational stability and electronic distribution.
- The study contributes to a deeper understanding of structure-property relationships in these heterocyclic compounds.
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