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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
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Resolving the Notorious Case of Conical Intersections for Coupled Cluster Dynamics.
Eirik F Kjønstad1,2, Henrik Koch1,2
1Department of Chemistry, Norwegian University of Science and Technology , 7491 Trondheim, Norway.
The Journal of Physical Chemistry Letters
|September 21, 2017
Summary
This study presents a new coupled cluster theory formulation to accurately model conical intersections in excited electronic states. This breakthrough enables precise simulations of photochemical events involving nonadiabatic dynamics.
Area of Science:
- Quantum chemistry
- Photochemistry
- Theoretical chemistry
Background:
- Conical intersections are crucial for electron-nuclear motion in photochemical events.
- These degeneracies act as funnels for nonadiabatic nuclear relaxation.
- Accurate quantum chemical models are vital for interpreting experimental data.
Purpose of the Study:
- To resolve a long-standing problem in coupled cluster theory.
- To develop the first formulation capable of describing conical intersections between excited electronic states of the same symmetry.
Main Methods:
- Utilizing ab initio quantum chemical models.
- Developing a novel coupled cluster theory formulation.
Main Results:
- The first accurate description of conical intersections between same-symmetry excited electronic states using coupled cluster theory.
- Demonstration of the theory's capability to handle nonadiabatic dynamics.
Conclusions:
- The developed coupled cluster theory accurately models conical intersections in excited states.
- This advancement extends the applicability of coupled cluster theory to photochemical dynamics.
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