XIAOYONG LIU, VADIM L. STAKHURSKY, ERIC D. OLMON, VLADIMIR A. LOZOVSKY, TERRY A. MILLER, C. BRADLEY MOORE, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, OH 43210.
Multimode Jahn-Teller analysis of the e modes in the X state of the CH3O radical has been initiated using the SOCJT program with special attention being paid to the asymmetric C-H stretch mode (n4) for which there are several relevant experimental observations. Dispersed Fluorescence (DF) spectra have been recorded via excitation of A 2A1 3n41 (n=1,2,3) combination levels for CH3O. DF spectra have also been obtained upon 3n(4')1 (n=1,2) LIF excitation for the CHD2O isotopomer. For both isotopomers the observed spectra reveal the quartet vibronic structure in the C-H stretch mode region. The observed quartet structure exhibits a large ( 130 cm-1 for CH3O and 160 cm-1 for CHD2O) separation; each component is further split into doublets ( 25 cm-1 and 35 cm-1 respectively for CH3O and CHD2O). In addition, the rotationally resolved structure of the 4 C-H stretch band of CH3O, recorded via stimulated emission pumping technique was compared with that recently obtained from IR spectra. The implications of the rovibronic structure for the vibronic assignments will be discussed.