Homogeneous nucleation and growth in iron-platinum vapour investigated by molecular dynamics simulation
Physical Chemistry, University of Cologne, Luxemburger Str. 116, 50939 Köln, Germany
Corresponding author: a firstname.lastname@example.org
Revised: 17 August 2006
Published online: 15 September 2006
Homogeneous nucleation and growth from binary metal vapour is investigated by molecular dynamics simulation. It is focused here mainly on the iron-platinum system with a mole fraction of 0.5. The simulations are started in the highly supersaturated vapour phase. Argon is added as carrier gas removing the heat of condensation from the forming clusters. The embedded atom method is employed for modelling of the force field of iron and platinum. The simulation runs are evaluated with respect to the nucleation rate, monomer temperature, monomer amount, and with respect to the size of the largest cluster in the system including possible pure metal clusters. It turns out that depending on the composition of the complete system pure platinum clusters with sizes up to 10 to 15 atoms are formed in addition to binary clusters. Due to the high temperature of these clusters iron atoms less likely condense at the beginning of the particle formation simulation. This leads to temporary difference in the temperatures of the platinum and the iron subsystems, which eventually approach each other when only binary clusters are present. In summary, the results obtained from the cluster statistics show that pure platinum nucleation and growth can take place to some extent within the binary system.
PACS: 36.40.-c – Atomic and molecular clusters / 71.15.Pd – Molecular dynamics calculations (Car-Parrinello) and other numerical simulations / 81.10.Aj – Theory and models of crystal growth; physics of crystal growth, crystal morphology, and orientation / 64.70.Nd – Structural transitions in nanoscale materials
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006