Measurements of photoelectron-photofragment angular correlation and energy partitioning in the dissociative photodetachment of ${\mathrm{O}}_4^{-}$ $({\mathrm{O}}_4^{-}+h\nu \to {\mathrm{O}}_2+{\mathrm{O}}_2{+e}^{-})$ at 532 nm are reported. Using photofragment translational energy and photoelectron spectroscopy in coincidence, vibrationally resolved product translational energy distributions and a pronounced angular correlation between the photoelectron and photofragment recoil directions are observed. These results provide insights into the molecule-fixed photoelectron angular distribution of a negative ion and structural information on ${\mathrm{O}}_4^{-}$ in the gas phase.

• Received 10 June 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.3335