Excitation of CO2 by Energy Transfer from Highly Vibrationally Excited Benzene Derivatives.

BEATRIZ M. TOSELLI; JOHN R. BARKER

AMER INST PHYSICS

Año: 1991 p. 8108 - 8108

he time-resolved infrared fluorescence technique has been used to study V-V and V-T /Renergy transfer to carbon dioxide from highly excited benzene, benzene-d6 , toluene, andtoluene-ds. The highly vibrationally excited aromatics in the electronic ground state areobtained by radiationless transitions after pumping with a KrF laser at 248 nm to the SIexcited electronic level. The V-V energy transfer from the excited parent to the asymmetricstretch mode of CO2 was measured by observing the characteristic emission of CO! near 4.3f.lm. From these measurements, the probability per collision of formation of COf wasdetermined as a function of the internal energy in the excited aromatic. In all casesinvestigated, this probability is ,0.1 % at the initial excitation energy of 40000 cm -1 and it isapproximately directly proportional to the vibrational energy of the excited aromatic. The totalconcentration of COf produced as a result of