PHOTOELECTRON-SPECTROSCOPY OF MANGANESE-SULFUR CLUSTER ANIONS

Manganese-sulfur cluster anions (MnnSm- n=1-10, m=1-10) have been stud ied using a magnetic-bottle type photoelectron spectroscopy (PES). The MnnSm- cluster anions were formed in a laser vaporization cluster sou rce. The most stable cluster anions were found to have the composition s of n=m and n=m+/-1. The electron affinities of neutral manganese sul fide clusters were measured from the onsets of the PES spectra, A new electronically excited state at 0.75 eV above the ground state was fou nd for MnS. From the size dependence of the PES spectra, it was found that Mn2S2-, Mn3S3-, and Mn4S4- are structural frameworks in MnnS2-, M nnS3-, and MnnS4- series, respectively. The electronic properties and geometrical structures of the clusters are discussed. (C) 1996 America n Institute of Physics.