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Baskes, Michael I

Publications and source records attributed to Baskes, Michael I.

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Generalized framework for interatomic potential design: Application to Fe–He system

Interatomic potentials play an important role in the physics of nanoscale structures. However, while interatomic potentials are designed for a specific purpose, they are often used for studying mechanisms outside of the intended purpose. Hence, a generalized framework for interatomic potential design is designed such that it can allow a researcher to tailor an interatomic potential towards specific properties. This methodology produces an interatomic potential design map, which contains multiple interatomic potentials and is capable of exploring different nanoscale phenomena observed in experiments. This methodology is effcient and provides the means to assessing uncertainties in nanostructure properties due to the interatomic potential fitting process. As an initial example, an Fe-He interatomic potential design map is developed using this framework to show its profound effect.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2011

Modeling ramp compression experiments using large-scale molecular dynamics simulation.

Molecular dynamics simulation (MD) is an invaluable tool for studying problems sensitive to atomscale physics such as structural transitions, discontinuous interfaces, non-equilibrium dynamics, and elastic-plastic deformation. In order to apply this method to modeling of ramp-compression experiments, several challenges must be overcome: accuracy of interatomic potentials, length- and time-scales, and extraction of continuum quantities. We have completed a 3 year LDRD project with the goal of developing molecular dynamics simulation capabilities for modeling the response of materials to ramp compression. The techniques we have developed fall in to three categories (i) molecular dynamics methods (ii) interatomic potentials (iii) calculation of continuum variables. Highlights include the development of an accurate interatomic potential describing shock-melting of Beryllium, a scaling technique for modeling slow ramp compression experiments using fast ramp MD simulations, and a technique for extracting plastic strain from MD simulations. All of these methods have been implemented in Sandia's LAMMPS MD code, ensuring their widespread availability to dynamic materials research at Sandia and elsewhere.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗