Non-adiabatic photoisomerization versus photodissociation dynamics of the chiral fluoroethylene derivative (4-methylcyclohexylidene) fluoromethane

作者：Alfalah Sherin; Kinzel Daniel; Gonzalez Vazquez Jesus; Gonzalez Leticia^*

来源：Chemical Physics, 2010, 369(2-3): 138-144.

DOI：10.1016/j.chemphys.2010.03.017

• Wavepacket dynamics
• Excited states
• Conical intersections
• Photodissociation
• Photoisomerization

The photoisomerization around the C=C double bond and the competing elimination of hydrogen fluoride (HF) are studied in (4-methylcyclohexylidene) fluoromethane. Both reactions are mediated by twisted conical intersections (CI) around the C=C bond. Potential energy surfaces (PES) for the electronic ground state and first bright excited state of pi pi* character are calculated using the CASSCF method along two reaction coordinates: the torsion around the C=C bond and the distance between the center of masses of the hydrocarbon moiety and the HF fragment. Non-adiabatic couplings between both PES are obtained at the same level of theory. Wavepacket dynamics on the coupled surfaces show that after light irradiation torsion in the pi pi* state dominates over HF dissociation, although the system starts with enough kinetic energy to reach the CI leading to HF-elimination.

• 出版日期2010-4-21