Resonance raman spectrum of the solvated electron in methanol: Simulation within a cluster model

The microsolvation of the CH₃OH₂ hypervalent radical in methanol clusters has been investigated by density functional theory. It is shown that the CH₃OH₂ radical spontaneously decomposes within methanol clusters into protonated methanol and a localized solvated electron cloud. The geometric and electronic structures of these clusters as well as their vibrational frequencies have been characterized. Resonance Raman intensities, associated with the s → p transition of the unpaired electron, have been estimated for CH₃OH₂M_n (M = CH ₃OH, n = 1-3) clusters. It is shown that with increasing cluster size the simulated spectra converge toward the resonance Raman spectrum of the solvated electron in methanol measured recently by Tauber and Mathies (J. Am. Chem. Soc. 2004, 126, 3414). The results suggest that CH₃OH ₂M_n clusters are useful finitesize model systems for the computational investigation of the spectroscopic properties of the solvated electron in liquid methanol.