Diffusion and Relaxation Dynamics in Cluster Crystals
2007; American Physical Society; Volume: 99; Issue: 10 Linguagem: Inglês
10.1103/physrevlett.99.107801
ISSN1092-0145
AutoresAngel J. Moreno, Christos N. Likos,
Tópico(s)Spectroscopy and Quantum Chemical Studies
ResumoFor a large class of fluids exhibiting ultrasoft bounded pair potentials, particles form crystals consisting of clusters located in the lattice sites, with a density-independent lattice constant. Here we present an investigation on the dynamic features of a representative example of this class. It is found that particles can diffuse between lattice sites, maintaining the lattice structure, through an activated hopping mechanism. This feature yields finite values for the diffusivity and full relaxation of density correlation functions. Simulations suggest the existence of a localization transition which is avoided by hopping and a dynamic decoupling between self- and collective correlations.
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