In this letter, the Peierls-Nabarro (PN) model is extended to describe dislocation mobility in piezoelectric materials. The Peierls stress of a screw dislocation in a piezoelectric material is calculated based on the generalized PN model and linear piezoelectricity theory. (C) 2004 American Institute of Physics.

A multiscale method is proposed. It combines the so-called bridging scale method and the perfectly matched layer method to form a robust and versatile multiscale algorithm. The method can efficiently eliminate the spurious reflections/diffractions from the artificial atomistic/continuum interface by matching the impedance at the interface of the molecular dynamic region and the perfectly matched layer. Moreover, it is shown in this paper that the method can capture anharmonic interaction among nonuniformly distributed atoms in a local region.