Molecular dynamics (MD) simulations with accurate, first principles-based interatomic potentials is a powerful tool to uncover and characterize the molecular-level mechanisms that govern the chemical, mechanical and optical properties of materials. Such fundamental understanding is critical to develop physics-based, predictive materials models and may help guide the design of new materials and devices with improved properties.
I will describe recent work on:
- Mechanical properties. We use MD with first principles-based interatomic potentials to characterize the molecular level mechanisms that govern plastic deformation of metals and molecular materials and how mechanical properties evolve when the characteristic size of the material is reduced to the nanoscale;
- Condensed-phase chemistry. Using MD with a new class of interatomic potentials that enable the description of chemistry we study the chemical and mechanical response of molecular energetic materials to shock- and thermal loading;
- Computational materials design. We use MD to design, optimize and characterize of a polymer-based nano-actuator. By way of controlling the device nano-structure at the molecular level we are able to achieve large electrostrictive strains (~5%) at extremely high frequencies (GHz), much higher than possible with today's materials.
In many applications it is necessary to go beyond the temporal and spatial scales of all-atom MD to predict the behavior of macroscopic materials or devices. I will describe recent progress in multi-scale modeling focused at upscaling the MD results via mesoscale modeling of molecular materials and micromechanical models of single crystal plasticity in metals.
Computer Sciences, Room 111