Collisionless Formation and Rovibronic Relaxation of CH and OH from the IR Multiphoton Photolysisof CH₃OH

Authors

Stephen E. Bialkowski, Utah State UniversityFollow
William A. Guillory

Document Type

Article

Journal/Book Title

Journal of Chemical Physics

Publication Date

1978

Volume

68

First Page

3339

Abstract

A CO₂ TEA laser has been used to initiate the collisionless multiphotondissociation of CH₃OH between 1000 and 10 mtorr. The appearance of OH(X  2Π i ) 50±20 nsec after the laser pulse, independent of initial CH₃OH pressure (50–200 mtorr), suggests the primary dissociative channel CH₃OH+n hν→CH₃ +OH(X  2Π i ); although CH₃ could not be correspondingly confirmed. The appearance of CH(X  2Π r ) 70±20 nsec after the OH(X) appearance, independent of initial CH₃OH pressure (70–400 mtorr), suggests secondary collisionless dissociation. Initial rovibronic distributions of OH(X) and CH(X) were determined, as well as characteristic decay time constants. The observation of the relaxation of OH(X) over a 10 μsec time interval after radical onset, allowed the separate characterization of collisional rotational relaxation and translational diffusion.

Recommended Citation

Collisionless Formation and Rovibronic Relaxation of CH and OH from the IR Multiphoton Photolysis of CH3OH Stephen E. Bialkowski and William A. Guillory Journal of Chemical Physics 68 3339 1978