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JUNE 26 MONDAY MORNING
RIV-TF-MoM-OR.3 EPITAXIAL MATCHING OF SMALL METALLIC NANO-
CLUSTERS IN LARGE-MISFIT SYSTEMS. J.C. Jiménez-Sáez. Departamento de Física y
Química Aplicadas a la Técnica Aeronáutica, E.U.I.T. Aeronáutica, Universidad Politécnica de Madrid
(UPM), E-28040 Madrid, Spain. E-mail: jc.jimenez@upm.es. A.M.C. Pérez-Martín and J.J.
Jiménez-Rodríguez. Departamento de Electricidad y Electrónica, Facultad de Ciencias Físicas, Universidad
Complutense, E-28040 Madrid, Spain.
The deposition at low energies of Cu and Au nanoclusters on the Au(001) and Cu(001) substrates respectively
is studied by constant temperature molecular-dynamics simulations. Clusters have icosahedral
or Wulff symmetries. Their number of atoms ranges between 13 and 1289. Atomic interactions
are mimicked by a many-body potential based on the tight-binding model. Deposition energy is
of the order of meV/atom and the temperature was 300 K. We have investigated the equilibrium
structure of deposited metallic clusters. The influence of the cluster size and of its shape in the lowenergy
limit on the epitaxial matching has been analyzed. We have taken into account the large lattice
misfit between the cluster and the substrate (12.8% for Cu/Au(001) and 11.35% for
Au/Cu(001)). Previous results show that in cases without misfit the epitaxial growth depends on the
size of the clusters and on the temperature as well. Besides in previous works, we have found a different
elastic behaviour in large clusters when deposition energy is lower or higher than 30
meV/atom. These differences can also induce variations in the epitaxial alignment between cluster
and substrate. The possible matching between both structures has been studied by the common
neighbour analysis, CNA, which classifies the types of bond; by both the structure factor and an epitaxy
factor which asses the degree of adaptation of both lattices; and finally, by a grain analysis
which allows to find out if the deposited-cluster lattice imitates the substrate lattice. Structural properties
of the interface (coherent, semicoherent or incoherent), in addition to the bond distances as a
function of the distance to the interface have been also investigated.
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