STRUCTURE AND SPECTROSCOPY OF PHOSPHORUS CLUSTER ANIONS - THEORY (SIMULATED ANNEALING) AND EXPERIMENT (PHOTOELECTRON DETACHMENT)

Photoelectron detachment measurements have been performed on singly ch arged phosphorus cluster anions with up to nine atoms, generated by a pulsed are cluster ion source (PACIS). Transitions between the anion g round states and states of the neutral clusters are observed for all c lusters, and vibrational fine structure in both dimer and trimer. A co mparison with the results of density functional calculations with simu lated annealing - an extension to negative ions of earlier work on neu tral and positively charged clusters - provides a consistent overall p icture for all cluster sizes and the first experimental structural inf ormation on several. (C) 1995 American Institute of Physics.