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Strain in layered nanocrystals

Published online by Cambridge University Press:  01 October 2007

Y. BAE
Affiliation:
ACMS, University of Arizona, Tucson, AZ, USA e-mail: byouri@acms.arizona.edu
R. E. CAFLISCH
Affiliation:
Department of Mathematics, UCLA, Los Angeles, CA, USA e-mail: caflisch@math.ucla.edu

Abstract

Layered nanocrystals consist of a core of one material surrounded by a shell of a second material. We present computation of the atomistic strain energy density in a layered nanocrystal, using an idealised model with a simple cubic lattice and harmonic interatomic potentials. These computations show that there is a critical size r*s for the shell thickness rs at which the energy density has a maximum. This critical size is roughly independent of the geometry and material parameters of the system. Interestingly, this critical size agrees with the shell thickness at which the quantum yield has a maximum, as observed in several systems and thus leads one to support the hypothesis that maximal quantum yield is strongly correlated with maximal elastic energy density.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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