C.R. Sherwood, M.C. Garner, K.A. Hanold, K.M. Strong and R.E. Continetti, "Energy and Angular Distributions in Dissociative Photodetachment of O4-", J. Chem. Phys. 102, 6949- 6952 (1995). An anisotropic product angular distribution has been observed in the dissociative photodetachment of O4- at 523 nm. Energy and angular distributions of coincident O2 products from the process O4- + hv --> O2 + O2 + e- were measured using translational energy spectroscopy in a fast ion beam. The angular distribution peaks perpendicular to the electric vector of the laser beam.