SYNCHROTRON-RADIATION STUDY OF MESOSCOPIC MANGANESE PARTICLES

We present a synchrotron radiation photoemission study of supported me soscopic manganese particles deposited in situ from a gas aggregation source. Investigations have been carried out on both mass-filtered and unfiltered particle beams. With the source conditions used the unfilt ered beam shows a log-normal distribution of particle sizes with the p eak at 2.5 nm. Mass selection was achieved by a quadrupole filter set to pass particles of 3.8 x 10(4) amu, i.e. at the peak of the distribu tion. Exposed Mn clusters deposited on highly oriented pyrolytic graph ite (HOPG) showed significant changes in the photoemission line shape of the 3s core level relative to bulk Mn, which is interpreted as an i ncrease in the atomic magnetic moment. Unfiltered Mn clusters were als o incorporated into a continuous Vanadium matrix to make a nano-scale granular film revealing a satellite structure in the photoemission spe ctrum of the V3s core level which we ascribe to a magnetic polarisatio n of the V atoms in the vicinity of the Mn clusters.