Investigation of the Short-time Photodissociation Dynamics of Furfural in S2 State by Resonance Raman and Quantum Chemistry Calculations

Raman (resonance Raman, FT-Raman), IR and UV-visible spectroscopy and quantum chemistry calculations were used to investigate the photodissociation dynamics of furfural in S2 state. The resonance Raman(RR) spectra indicate that the photorelaxation dynamics for the S0→S2 excited state is predominantly along nine motions: C=O stretch ν5 (1667 cm−1), ring C=C antisymmetric stretch ν6 (1570 cm−1), ring C=C symmetric stretch ν7 (1472 cm−1), C2-O6-C5 symmetric stretch/C1-H8 rock in plane ν8 (1389 cm−1), C3-C4 stretch/ C1-H8 rock in plane ν9 (1370 cm−1), C5-O6 stretch in plane ν12 (1154 cm−1), ring breath ν13 (1077 cm−1), C3-C4 stretch ν14 (1020 cm−1), C3-C2-O6 symmetric stretch ν16 (928 cm−1 ). Stable structures of S0 ,S1 ,S2 ,T1 and T2 states with Cs point group were optimized at CASSCF method in Franck-Condon region there are S2/S1 conical intersection was found by state average method and RR spectra.