Regensburg 2004 – wissenschaftliches Programm
O 10.4: Vortrag
Montag, 8. März 2004, 16:30–16:45, H43
Quenching of surface magnetic moments in rare gas isolated Ni clusters — •Kai Fauth1,2, Markus Heßler1,2 und Gisela Schütz2 — 1Physikalisches Institut der Universität Würzburg, Am Hubland, 97074 Würzburg — 2MPI für Metallforschung, Heisenbergstraße 3, 70569 Stuttgart
X-ray magnetic circular dichroism (XMCD) is a method well
suited for the element specific analysis of magnetic moments in
transition metals. The XMCD technique allows their
quantitative analysis in terms of spin and orbital contributions.
The application of XMCD to small clusters is only possible
if these are deposited on a substrate. Their deposition into rare gas
matrices is the best possible approximation to noninteracting clusters.
While this approach is succesful in the
case of Fe and Co clusters, we show here that the same is not
true in the case of small Ni clusters. The observed
magnetizations are by far smaller than expected. Their size
dependence suggests a quenching of the magnetic Ni moments to
occur at the cluster surface, induced by the presence of the Ar
environment. Similar results were theoretically obtained previously for Ni
clusters encapsulated by a He shell .
G. Pacchioni, S. C. Chung, S. Krüger and N. Rösch, Chem. Phys. 184, 125 (1994)