Transient grating study on vibrational energy relaxation of bridged azulene–anthracene’s

A transient grating study of intermolecular vibrational energy dissipation in competition with intramolecular vibrational energy re-distribution (IVR) is reported. The translational temperature rise rates of 1-alkylazulene and 1-(anthracene-9-yl-alkyl)azulene in organic solvents are compared with the kinetics obtained from transient absorption (TA) experiments [D. Schwarzer, P. Kutne, C. Schroder, J. Troe, J. Chem. Phys. 121 (2004) 1754]. The results of 1-alkylazulene suggest the dynamics assigned to IVR in the TA study could complete with the temperature rise kinetics of the solvent. The results of 1-(anthracene-9-yl-alkyl)azulene support the existence of the faster dissipation process than TA component. The different solvent effects are also discussed.