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Vibrational Properties of 2D Copper Islands on the CU(111) Surface by MD Simulations

  • E. Vamvakopoulos
  • G. A. Evangelakis
Chapter
Part of the NATO Science Series book series (NAII, volume 65)

Abstract

Using molecular dynamics simulations based on an effective potential in analogy to the tight-binding theory in the second-moment approximation, we have studied the vibrational behaviour of various 2D Cu islands on the Cu(111) surface. We found that, in the direction normal to the surface, the mean-square-displacements of the island atoms do not depend on the size of the island, but are increased by a factor of five in the in-plane directions. These findings are compatible with the behaviour of the cluster phonon modes. Indeed, we found that small islands introduce new vibrational modes that diminish with increasing cluster size beyond a certain critical size (N > N C ), eventually recovering the surface vibrational behaviour. This characteristic size, N C , coincides with the island size above which the migration energy of the island atoms saturates to the value of the step energy barrier.

Keywords

Vibrational Property Island Size Phonon Density Surface Direction Increase Cluster Size 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 2002

Authors and Affiliations

  • E. Vamvakopoulos
    • 1
  • G. A. Evangelakis
    • 1
  1. 1.Department of Physics, Solid State DivisionUniversity of IoanninaIoanninaGreece

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