Coarse-grained molecular dynamics for design of nanomechanical systems

We give an overview of some of the unique challenges for computer modeling and simulation that arise from the development and design of nanoscale mechanical systems. Of particular interest are the dynamic and temperature-dependent processes found in nanomechanical systems. We focus on the behavior of sub-micron mechanical components of Micro-Electro-Mechanical Systems (MEMS), especially micro-resonators. The coupling of length scales methodology we have developed for MEMS employs an atomistic description of millions of atoms in relatively small but key regions of the system, coupled concurrently to a generalized finite element model of the periphery. The model, Coarse-Grained Molecular Dynamics (CGMD), describes the dynamics on a mesh of elements, but the equations of motion are built up from the underlying atomistic physics to ensure a smooth coupling between regions governed by different length scales.