Surface segregation in bimetallic nanoclusters

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Surface segregation in bimetallic nanoclusters

• Daniela S. Mainardi, Margaret R. Lewis and Perla
  B. Balbuena

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• Monte Carlo simulations based on the
  bond-order-simulation model (DS Mainardi and PB
  Balbuena, Langmuir, 2001, Int. J. Quantum Chem.,
  2001)
• fcc cluster with fixed geometry.
• Energy minimization to determine surface
  composition as a function of cluster size, shape,
  overall composition, temperature.

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D. S. Mainardi and P. B. Balbuena, Langmuir
(2001), Int. J. Quant. Chem. (2001)
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Fraction of silver atoms on the (hkl) surface of
a cluster with NT atoms
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Effect of surface energies on surface segregation
in nanoclusters (From Margaret R. Lewis Honors
College Thesis, 2002)
The fraction of segregating atoms (Ag) in
each layer for the four-layer NiAg cluster. Note
Ag segregation to the top and bottom layers .
The surface site energy of Ni has been modified
from 3.82 eV to -4.06 eV to determine the effect
of this variation on surface segregation.