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Updated: Jan 10, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Control of Conical Intersection Dynamics in CF3I Photodissociation via Halogen Bonding
Dong Yan1, Huimin Zhang2,3, Fangfang Li1,4
1Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Porous Materials for Separation and Conversion, Fudan University, Shanghai 200438, P. R. China.
JACS Au
|November 28, 2025
Summary
Halogen bonding offers a novel method to control chemical reactions by influencing conical intersection dynamics. This study demonstrates how halogen bonding alters photodissociation pathways of CF3I, enabling precise control over reaction outcomes.
Area of Science:
- Chemical Dynamics
- Noncovalent Interactions
- Photochemistry
Background:
- Conical intersections are crucial in photoexcited polyatomic systems, dictating chemical reaction pathways.
- Controlling conical intersection dynamics remains a significant challenge in reaction dynamics.
Purpose of the Study:
- To investigate the influence of halogen bonding on the conical intersection dynamics of halogenated compounds.
- To demonstrate a method for controlling chemical reaction pathways using noncovalent interactions.
Main Methods:
- Time-sliced ion velocity map imaging was used to study the ultraviolet photodissociation of CF3I.
- Experiments were conducted with CF3I interacting with N2, CO, and C2H4 in supersonic molecular beams.
- Theoretical calculations were performed to elucidate the electronic structure changes at conical intersections.
Main Results:
- Significant alterations in product velocity and angular distributions of I-(2P3/2) were observed.
- Product branching ratios of I-(2P3/2) to I*(2P1/2) varied substantially (0.10 to 0.71) due to halogen bonding.
- Halogen bonding was found to elevate curve-crossing energies, reducing product velocities and enhancing specific reaction channels.
Conclusions:
- Halogen bonding effectively controls conical intersection dynamics in halogenated compounds.
- This study presents a "soft chemical control" strategy for regulating photochemical reactions.
- The findings highlight the importance of noncovalent interactions in manipulating nonadiabatic transition dynamics.
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