15min:

TIMOTHY A. BARCKHOLTZ, DAVID E. POWERS AND TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, Columbus, Ohio 43210.

The two-color \left( 1+1'\right) REMPI and ZEKE spectra of the ZnCH₃ and MgCH₃ radicals have been obtained. The ZnCH₃ radicals were generated in a supersonic free jet expansion by ArF excimer photolysis of Zn(CH₃)₂ while MgCH₃ was generated by ablation of a Mg rod in the presence of a methyl source, generally either Sn(CH₃)₄ or CH₃CN. The ZEKE spectra, taken via various intermediate vibronic levels of the \widetildeA ²E state, are used to reveal the vibrational structure of the ZnCH₃ and MgCH₃ cations and to measure the adiabatic ionization energy for each radical. These radicals belong to the C_3v point group and are therefore subject to a Jahn-Teller interaction in the \widetildeA state, which allows a broader range of vibrational states to be accessible in the LIF and REMPI experiments, thereby enabling access to a broader range of vibrational states for the ions in the ZEKE experiment. Vibrational frequencies and assignments of the ions will be reported.