Ultraviolet photoelectron spectroscopy and photofragmentation studies of excess electrons in potassium iodide cluster anions

Abstract

Ultraviolet photoelectron spectroscopy (UPS) and photofragmentation data for (KI)−n, K(KI)−n , and K2(KI)−n (n up to 13) are presented. The excess electrons in these clusters are all loosely bound with vertical detachment energies below 1.6 eV, and the photofragmentation data correlated well with the UPS results. Our results for the stoichiometric clusters are in good agreement with theoretical predictions, and the ground state geometry of these clusters are discussed. For the excess potassium cluster series, we suggest the possible existence of electron spin pairs in some of these cluster anions.