DIRECT MEASUREMENTS OF STATE-SPECIFIC UNIMOLECULAR DISSOCIATION RATE CONSTANTS OF HIGHLY EXCITED SINGLE ROTATION-VIBRATION QUANTUM STATES OF CH3O ((X)OVER-TILDE(2)E)

Vibration rotation quantum state resolved unimolecular dissociation li fetimes of highly excited CH3O (X 2E) molecules have been measured usi ng the method of stimulated emission pumping (SEP) in connection with transient laser induced fluorescence (TLIF) excitation spectroscopy fo r preparing selected single target states and for their time resolved detection. The measured decay rate constants for six closely spaced le vels with precisely known total excitation energies around E(X) almost -equal-to 7450 cm-1 and J = 0.5 (or 1.5) were found to vary erraticall y between 9.10(5) s-1 less-than-or-equal-to k less-than-or-equal-to 3. 10(7) s-1. The results are compared to predictions by unimolecular rat e theory and discussed with respect to the question of mode specific v s statistical reactivity.