Resonance Raman and density functional theory investigation of the photodissociation dynamics of the A-band absorption of (E)-Β-nitrostyrene in cyclohexane solution

Abstract

Resonance Raman spectra were obtained for (E) -Β -nitrostyrene in cyclohexane solution with excitation wavelengths in resonance with the charge transfer (CT)-band absorption spectrum. These spectra indicate that the Franck-Condon region photodissociation dynamics have multidimensional character with motion predominantly along the nominal N O2 symmetric stretch mode (14), the nominal CC stretch mode (8), the nominal benzene ring stretch mode (9), accompanied by a smaller amount of motion along the nominal ONO symmetric bend/benzene ring stretch mode (34), the nominal CCH in-plane bending mode (20), the nominal HCCH in-plane bending mode (18), the nominal N O2 asymmetric stretch mode (11), the nominal C-N stretch/benzene ring breathing mode (27), and the nominal CCC trigonal bending mode (25). A preliminary resonance Raman intensity analysis was done and these results for (E) -Β -nitrostyrene were compared to results previously reported for several nitrobenzene and trans-stilbene compounds. The differences and similarities between the CT-band resonance Raman spectra and vibrational reorganizational energies for (E) -Β -nitrostyrene relative to those for nitrobenzene and trans-stilbene were briefly discussed. © 2007 American Institute of Physics.