Bilinear Jahn–Teller coupling effects in the methoxy radical: impact on photoelectron spectra and spin–orbit splittings

Abstract

A previous theoretical investigation of the multimode dynamical Jahn–Teller effect in the methoxy radical is extended to calculate the vibrational structure of the first bands of the photoelectron spectra of CH 3O − and CD 3O − and to include the effects of spin–orbit coupling. Bilinear coupling terms between the e and a 1 vibrational modes are shown to be of major importance for the spectral intensities; they also lead to a marked dependence of the spin–orbit splittings on the quantum numbers of the a 1 modes in the electronic ground state of the radical.