MOLECULAR ELEMENT METHOD (MEM) FOR MULTI-SCALE MODELING AND SIMULATIONS OF NANO/MICRO-SYSTEMS

Abstract

A new technique called Molecular Element Method is proposed for multi-scale modeling and simulations of nano/micro-systems. In this technique, the system is divided into molecular elements whose properties are represented by sets of equivalent physical parameters obtained from atomic information. The discrete system is solved based on continuum mechanics theories. The resultant element information from system solving is then used as an external constraint for the elements, to investigate the atomic information within, using molecular dynamics calculations. Both system properties and atomic information at local zones can be obtained accurately and efficiently in this way, A crystal of Cu having 285,883 atoms with a through the thickness hole inside is investigated using this technique. Tension stresses of the crystal and the slip of atoms around the hole’s edge are revealed corresponding to five strain loads. Compared with the results obtained from the classical molecular dynamics method, the maximum stress error is 2.7%, while the computational time is only 7.2-11.8% of that taken by the classical method.