Los Alamos National Laboratory – Page 3

Accelerating Molecular Dynamics Simulations

Germann T.C., Voter A.F., Los Alamos National Laboratory, US

In contrast with the converging length scales of atomistic simulations and experimental nanoscience, large time scale discrepancies still remain, due to the time-scale limitations of molecular dynamics. We briefly review two recently developed methods, derived [...]

Temperature Accelerated Dynamics: Introduction and Application to Crystal Growth

Montalenti F., Los Alamos National Laboratory, US

Temperature accelerated dynamics (TAD) simulations allow one to reach long time scales without needing any a priori information on the system dynamics. As a consequence, TAD is a powerful method for simulating complex phenomena where [...]

Introduction to the Time Scale Problem

Voter A.F., Los Alamos National Laboratory, US

As motivation for the symposium on extended-scale atomistic methods, I briefly discuss the time scale problem that plagues molecular dynamics simulations, some promising recent developments for circumventing the problem, and some remaining challenges.

Molecular Modeling of Proton Conduction in Polymer Electrolyte Membranes of Nafion® Type

Paddison S.J., Eikerling M., Zawodzinski_Jr. T.A., Pratt L.R., Los Alamos National Laboratory, US

Molecular mechanisms of proton conduction in polymer electrolyte membranes are addressed by ab initio molecular dynamics calculations, utilizing the VASP program, on the model system trifluoromethane sulfonic acid monohydrate solid. After establishing that the experimental [...]

Report on the Modeling of the Large MIS Cans

Moody E.W., Lyman J., Veirs D.K., Los Alamos National Laboratory, US

Changes in gas composition and gas pressure for closed systems containing plutonium dioxide and water are studied using a model that incorporates both radiolysis and chemical reactions. The model is used to investigate the behavior [...]

3D Modeling of Metallic Grain Growth

George D., Carlson N., Gammel J.T., Kuprat A., Los Alamos National Laboratory, US

This paper will describe simulating metallic grain growth using our Gradient Weighted Moving Finite Elements code, GRAIN3D. We also describe the set of mesh topology change operations developed to respond to changes in the physical [...]

TopoSim3D/Grain3D: Modeling Surface Deposition and Growth

Gammel J.T., Walker R., Los Alamos National Laboratory, US

We discuss the coupling we are develping between TopoSim3D and Grain3D - two tols making use of the Los Alamos LaGriT adaptive grid toolset. TopoSim3D is a three-dimensional profile simulation tool being developed at Los [...]

Capacitance Extraction from Complex 3D Interconnect Structures

Cartwright D., Csanak G., George D., Walker R., Kuprat A., Dengi A., Grobman W., Los Alamos National Laboratory, US

A new tool has been developed for calculating the capacitance matrix for complex 3D interconnect structures involving multiple layers of irregularly shaped interconnect, imbedded in different dielectric materials. This method utilizes a new 3D adaptive [...]

Molecular Dynamics (MD) Simulations of Reactive Ion Etching (RIE) of Silicon by Cl, Cl2, Br and Br2 Cations

Valone S.M., Hanson D.E., Kress J.D., Los Alamos National Laboratory, US

Simulations of Cl plasma etch of Si surfaces with MD techniques agree reasonably well with the available experimental information on yields and surface morphologies. This information has been supplied to a Monte Carlo etch profile [...]