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Direct Signature of Light-Induced Conical Intersections in Diatomics
G J Halász1, Á Vibók2, L S Cederbaum3
1†Department of Information Technology, University of Debrecen, P.O. Box 12, H-4010 Debrecen, Hungary.
The Journal of Physical Chemistry Letters
|August 12, 2015
Summary
Researchers discovered laser-induced conical intersections (LICIs) in D2+ molecules. A unique photofragment angular distribution provides direct evidence for these LICIs, impacting molecular dynamics.
Area of Science:
- Molecular physics and quantum chemistry
- Investigating nonadiabatic effects in molecular systems
Background:
- Nonadiabatic effects are crucial in molecular dynamics, often amplified by conical intersections (CIs).
- Conical intersections (CIs) are degeneracies between electronic states in molecules with three or more atoms.
- Laser-induced conical intersections (LICIs) can form even in diatomic molecules, significantly altering molecular behavior.
Purpose of the Study:
- To provide direct evidence for the existence of laser-induced conical intersections (LICIs).
- To analyze the impact of LICIs on molecular photodissociation dynamics.
Main Methods:
- Detailed analysis of the photodissociation process in the D2+ molecule.
- Examination of photofragment angular distributions as a signature of molecular dynamics.
Main Results:
- A robust effect was identified in the angular distribution of photofragments from D2+ photodissociation.
- This observed effect serves as a direct signature, confirming the existence of LICIs.
Conclusions:
- The study provides undoubted evidence for laser-induced conical intersections (LICIs) in molecular systems.
- The findings demonstrate that LICIs can significantly influence molecular dynamics, as evidenced by photofragment angular distributions.
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