15min:

JINJUN LIU, JOHN T. YI, VADIM STAKHURSKY AND TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210; DMITRY MELNIK AND ROBERT F. CURL, Department of Chemistry and Rice Quantum Institute, Rice University, Houston, TX 77005.

The methoxy radical, CH₃O, is one of the most interesting and most widely-studied free radicals. It provides a benchmark case of the Jahn-Teller effect in a molecule with spin-orbit interaction. The partial deuteration of the methoxy radical breaks the molecular symmetry, thereby reducing the electronic orbital angular momentum in the X²E ground state by introducing new terms in the rovibronic Hamiltonian of CH₃O. The resolved rotational and fine structure in the LIF spectra of CHD₂O and CH₂DO has been assigned and analyzed by simulating and fitting the 3₀ ² and (6')₀ ¹ bands of the A²A₁--X²E_3/2 transition for each isotopomer, providing molecular constants and energy levels for both states of each isotopomer. The ground state results were used to predict the previously observed X state microwave spectrum. This prediction is consistent within the experimental accuracy of the LIF experiment. As an additional control, the 3₀² and 6₀¹ bands of the A²A₁--X²E_3/2 transition for CH₃O and CD₃O were analyzed using the same method. Efforts are underway to fit simultaneously the LIF, microwave, and possibly SEP data of the ground state of these isotopomers to a rotational and fine structure Hamiltonian.