Defects and structural disorder in nanoclusters of Au, Zn, Cd, Pb.
Theoretical and experimental information on the shape and morphology of Au, Ag, Zn, Cd clusters is fundamental to predict and understand their electronic, optical, and other physical and chemical properties. An effective theoretical approach to determine the lowest-energy configuration (global minimum) and the structures of low energy isomers (local minima) of clusters is to combine genetic algorithms and many-body potentials (to perform global structural optimizartions), with first-principles density functional theory (to confirm stability and energy ordering of the local minima).
The main trend emerging from structural optimizations of bare Au clusters, for example, in the size range of 12-122 atoms indicates that many topologically interesting lowest-symmetry, disordered structures exist with energy near or below the lowest-energy ordered isomer. For example, chiral structures have been obtained as the lowest energy isomers of bare Au28 and Au55 clusters, whereas in the size-range of 75-212 atoms, defective Marks decahedral structures are nearly degenerate in energy with the ordered symmetrical isomers.
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I.L. Garzón, Michaelian, M.R. Beltran, A. Posada-Amarillas, P. Ordejon, E. Artacho, D. Sanchez-Portal, and, J.M. Soler
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K. Michaelian, N. Rendon, and, I.L. Garzón
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K. Michaelian, M.R. Beltran, and, I.L. Garzón
Phys. Rev. B 65, 041403R (2002).
Copyright © 2009 Ignacio L. Garzón All Rights Reserved.
Last Update: February 9, 2009 | Arzate Mary Carmen | Contact