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The synthesis, as well as the structure and magnetic moments of the mass-filtered 3d transition metal nanoparticles are discussed. The nanoparticles are found to exhibit strong bulklike total magnetic moments, in addition to the enhanced orbital moments exhibited by the iron nanoparticles.

This investigation turns its attention to magnetic effects of cobalt islands on a non-magnetic substrate. The preparation technique of MBE enables the creation of flat and well-ordered surfaces of hcp-Co(0001) if the evaporation onto a W(110) crystal is carried out at ambient temperatures. Subsequent heating to about 1000 K causes a phase transition from thin films to islands. The investigations are carried out in VUV photoemission with polarized synchrotron radiation, LEED and Scanning Tunneling Microscopy (STM). We employ the technique of magnetic linear dichroism in the angular distribution of photoemission (MLDAD) from valence bands. The MLDAD effect shows significant differences between a flat cobalt layer and cobalt islands. Variations due to the excitation energies are discussed with respect to a fully-relativistic bulk-band-structure calculation. [ABSTRACT FROM AUTHOR]

Carbon and metal clusters are excited by strong femtosecond laser pulses with up to 1016 W/cm2, yielding ionized clusters and highly charged atomic ions. For small carbon clusters and fullerenes the abundance of charged species correlates with the laser power, while for metal clusters the ionization efficiency is additionally strongly affected by the chosen laser pulse width which may result in an enhanced up–charging of the metal particle. In the case of platinum atomic charge states up to z=20 are detected at a pulse duration of about 600 fs. This observation is in accordance with a model based on a multi–plasmon excitation process. [ABSTRACT FROM AUTHOR]

Focuses on a Wein filter used for the mass analysis of small and large metal cluster ions. Theoretical considerations involved in the filter; Model for the cluster velocity after a supersonic expansion; Initial kinetic energy of small clusters; Wien filter spectra; Off axis detection.