The ground state band obtained by photodetachment at 266 nm is shown in Figure . From the vibrational origin, labeled 0 0 0 , we obtained an electron affinity (EA) of 3.937 eV for the NO3 radical. This band also reveals considerable vibrational structure. Peak b, lying 1057 cm -1 above the vibrational origin, was assigned to the 1 0 1 transition based on the 1 symmetric stretch frequency inferred from dispersed fluorescence from the NO3 2 BE  state. Most surprising, however, was the observation of a progression of peaks spaced by 360 cm -1 , assigned to transitions involving the 4 in-plane bend as indicated in Figure . In the D3h point group, this is a non-totally symmetric mode with e ' symmetry.