Slow electron velocity-map imaging photoelectron spectra of the methoxide anion

High resoln. anion photodetachment spectra are presented for the methoxide anion and its fully deuterated counterpart. The spectra were obtained with slow electron velocity-map imaging. Improved electron affinities are detd. for CH3O as 1.5690 +- 0.0019 eV and for CD3O as 1.5546 +- 0.0019 eV. The spectra resolve many features assocd. with spin-orbit and vibronic coupling that were not seen in previous photodetachment studies. Photoelectron angular distributions taken as a function of detachment wavelength for the ground vibronic state transitions are recorded and are consistent with the removal of a nonbonding, p-type electron localized on the oxygen atom. Several hot bands and sequence bands are obsd. for the first time, providing insight into the vibrational structure of the methoxide anion. The results are compared to recent calcns. of the anion photoelectron spectra that incorporate bilinear coupling terms among the methoxy vibrational modes and are found to be in reasonable agreement. [on SciFinder (R)