			15min:

THEORETICAL PREDICTION OF THE ROTATIONAL CONSTANTS FOR PROTONATED METHANOL (CH₃OH₂⁺): A MISSING PLAYER IN HOT CORE CHEMISTRY.

D. E. WOON, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana IL 61801.

Protonated molecules play important roles in the ion-molecule chemistry of hot cores. Protonated methanol, CH₃OH₂⁺, is thought to contribute significantly to the gas phase formation of other known organic species such as methyl formate and dimethyl ether. While the protonated forms of many of the most common astromolecules have previously been detected, CH₃OH₂⁺ remains unidentified to date due to the absence of an experimental rotational spectrum. In order to provide theoretical predictions to assist anticipated new laboratory work, various levels of quantum chemical methodology were employed to predict the structure of CH₃OH₂⁺ and to convert its equilibrium rotational constants to A₀, B₀, and C₀. Potentials for the inversion and rotation of OH₂⁺ with respect to the CH₃ group were also determined. This work built upon a benchmark study of methylamine discussed elsewhere (INSERT CODE).