Multiscale Stress Analysis Using EDIP Silicon

It is necessary to be able to seamlessly meld molecular dynamics (MD) and continuum stress analysis in many engineering situations. In this paper, we developed a finite volume method (FVM) to solve the continuum stress problem, while the MD simulation employs the environmentally dependent inter-atomic potential (EDIP), a three-body potential suitable for modeling silicon. Fixed-free and fixed-fixed bar bending problems are simulated by both the FVM method and the MD EDIP simulation. The results from the two computations are seen to match well for a cantilever of 32.136times5.43times5.43 nm³. A one-way multiscale analysis is then performed . Here, the FVM simulation is carried out in the whole domain, while the MD simulation is performed in a sub-domain, with an overlap region in which MD and continuum models are both employed. Material velocities computed by the continuum solution are interpolated to the atomic positions in the MD solver, but velocities from the MD solution do not influence the continuum solution. The method is applied to the beam bending problem and a reasonable match with the pure MD, pure continuum and the multiscale simulation is found