The excited state dynamics study of di-2-pyridylketone in the A-band and B-band absorptions by using resonance Raman spectroscopy, IR and UV-visible spectroscopy

Excitation wavelengths of 282.4, 273.9 (A band), 252.7, 239.5 and 228.7?nm (B band) resonance Raman spectra were acquired for di-2-pyridylketone, and density functional calculations were carried out to help in the elucidation of the photo relaxation dynamics of A-band and B-band electronic transitions. The resonance Raman spectra show that the intensity pattern of the A band presents great difference from that of the B band, which indicate that the short-time A-band (S0?S4) photo relaxation dynamics have substantial difference from that of B band (S0?S10) . The overall picture of short-time dynamics and the vibronic coupling mechanisms are interpreted using Albrecht's theory. Copyright (c) 2012 John Wiley & Sons, Ltd.