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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Ab initio quantum dynamical study of photoinduced ring opening in furan
E V Gromov1, C Lévêque, F Gatti
1Theoretische Chemie, Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany.
The Journal of Chemical Physics
|November 4, 2011
Summary
This study investigates furan
Area of Science:
- Theoretical Chemistry
- Photochemistry
- Quantum Dynamics
Background:
- Furan's excited singlet states are crucial for understanding its photochemical reactivity.
- Nonadiabatic processes govern ultrafast reactions in molecules.
Purpose of the Study:
- To investigate the nonadiabatic photoinduced ring opening in furan's lowest excited singlet states.
- To elucidate the role of potential energy surfaces and nuclear dynamics in this photoreaction.
Main Methods:
- Ab initio computations using the equation-of-motion coupled cluster method (EOM-CCSD).
- Wave-packet propagation techniques considering up to five nuclear degrees of freedom.
- Analysis of nonadiabatic coupling and conical intersections.
Main Results:
- Electronic population transfer occurs on a timescale of approximately 10 femtoseconds (fs).
- Out-of-plane bending mode is critical for state interaction and photoreaction.
- The estimated lifetime for the ring-opening process is around 2 picoseconds (ps).
Conclusions:
- The theoretical investigation provides insights into the mechanism of furan's photoinduced ring opening.
- The study highlights the importance of nonadiabatic effects and specific nuclear motions.
- The lifetime is dependent on the dimensionality of the quantum dynamical treatment.
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