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Exploring Orthogonality between Halogen and Hydrogen Bonding Involving Benzene
Alessandra Forni1, Rosario Russo2, Giacomo Rapeti2
1Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"-CNR, INSTM RU, Via Golgi 19, 20133 Milan, Italy.
Molecules (Basel, Switzerland)
|December 10, 2021
Summary
Orthogonality between halogen and hydrogen bonding is not absolute. Computational studies show these interactions with a benzene π-system are interdependent, challenging the notion of strict energetic independence.
Area of Science:
- Chemical Physics
- Computational Chemistry
- Molecular Interactions
Background:
- The concept of orthogonality between halogen and hydrogen bonding is established in chemistry.
- Previous studies focused on carbonyl oxygen as a shared acceptor.
Purpose of the Study:
- To investigate the interdependence of halogen and hydrogen bonding with a shared π-electron system.
- To evaluate the validity of strict orthogonality in these interactions.
Main Methods:
- Density Functional Theory (DFT) calculations using M06-2X, M11, ωB97X, and ωB97XD functionals.
- Utilized the aug-cc-PVTZ basis set for high accuracy.
- Examined interactions with a benzene π-electron system using NCBr and H2O as donors.
Main Results:
- Halogen and hydrogen bonding with benzene are not energetically independent.
- The geometry (double T-shaped or perpendicular) influences the interdependence.
- The findings challenge the universally accepted orthogonality concept.
Conclusions:
- The orthogonality between halogen and hydrogen bonding requires careful evaluation based on the specific acceptor group.
- Energetic independence of these interactions is not guaranteed, especially with π-systems.
- This study refines the understanding of non-covalent interactions.
Keywords:
DFT calculationshalogen bondinghalogen-π interactionhydrogen bondingorthogonal interactionsMore Related Videos
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