Journal of Chemical Physics, Vol.106, No.23, 9810-9814, 1997
Photoionization Studies of Manganese Clusters - Ionization-Potentials for Mn-7 to Mn-64
The photoionization spectra of manganese clusters consisting of between seven and sixty-four atoms have been measured near threshold. As for other transition metal clusters previously investigated, the ionization potentials (IPs) decrease rapidly but nonmonotonically up to n congruent to 20 and more slowly and smoothly beyond that. No correlation is observed between Mn, IPs and their reactivity toward molecular hydrogen, reported previously by Parks et al. [J. Chem. Phys. 104, 3531 (1996)]. In particular, the absence of any discontinuity in IP at Mn-16 suggests that the onset of reactivity toward hydrogen noted at that size is not due to a sudden change in electronic structure (e.g., a nonmetal-to-metal transition), but rather to a change in cluster geometry.
Keywords:TRANSITION-METAL CLUSTERS;PHOTOELECTRON-SPECTROSCOPY;NIOBIUM CLUSTERS;ELECTRONIC-STRUCTURE;IRON CLUSTERS;REACTIVITY;DEPENDENCE;PARTICLES;ENERGIES;BINDING