Wave propagating across atomic–continuum interface

Abstract

Motivated by eliminating the spurious wave reflection at the interface between atomic and continuum domains in the multiscale modeling and simulation, we present a novel numerical approach for the atomistic field theory without any special treatment at the interfaces. This novel approach abandons the method to calculate the finite element nodal forces in the continuum domain based on the strain–stress relation. Instead, it employs the interatomic forces as in molecular dynamics simulation. This nonlocal procedure overcomes the force mismatch between atomic and continuum domains and enables a seamless scale transition between fully atomistic resolution and continuum description. Meanwhile, to balance the trade-off between computational efficiency and numerical accuracy, we adopt a cluster-based sampling scheme which allows a group of unit cells around every nodal point to contribute to the calculation of nodal forces. Numerical results show that this novel numerical procedure drastically reduces the wave reflection at the atomic–continuum interface.

Keywords:

• wave propagation
• multiscale material modeling
• atomic–continuum interface
• nanomechanics
• atomistic field theory