Coarse-grained molecular dynamics: Nonlinear finite elements and finite temperature

By R. Rudd, J. Broughton. 2005

154 citations recorded by the source corpus.

Coarse-grained molecular dynamics (CGMD) is a technique developed as a concurrent multiscale model that couples conventional molecular dynamics (MD) to a more coarse-grained description of the periphery. The coarse-grained regions are modeled on a mesh in a formulation that generalizes conventional finite element modeling (FEM) of continuum elasticity. CGMD is derived solely from the MD model, however, and has no continuum parameters. As a result, it provides a coupling that is smooth and provides control of errors that arise at the coupling between the atomistic and coarse-grained regions. In this paper, we elaborate on the formulation of CGMD, describing in detail how CGMD is applied to anharmonic solids and finite-temperature simulations. As tests of CGMD, we present in detail the calculation of the phonon spectra for solid argon and tantalum in three dimensions, demonstrating how CGMD provides a better description of the elastic waves than that provided by FEM. We also present elastic wave scattering calculations that show the elastic wave scattering is more benign in CGMD than FEM. We also discuss the dependence of scattering on the properties of the mesh. We introduce a rigid approximation to CGMD that eliminates internal relaxation, similar to the quasicontinuum technique, and compare it to the full CGMD.

Subfields: Ceramics and Composites, Geophysics, Mechanics of Materials

View Paper: https://www.semanticscholar.org/paper/194cb725d9b0267646230d591ff8bdf6e3569954

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Ceramics and Composites

1. Ellad B. Tadmor
2. Jitesh H. Panchal
3. Surya R. Kalidindi
4. David L. McDowell
5. Ronald E. Miller

In Geophysics

1. Ronald E. Miller
2. Ellad B. Tadmor
3. Jitesh H. Panchal
4. Surya R. Kalidindi
5. David L. McDowell
6. Jacob Fish
7. Zheng Yuan
8. Markus J. Buehler

In Mechanics of Materials

1. Surya R. Kalidindi
2. David L. McDowell
3. Jitesh H. Panchal
4. Ellad B. Tadmor
5. Ronald E. Miller
6. Franz Roters
7. Dierk Raabe
8. Michael D. Sangid

Citations in the corpus

• Key computational modeling issues in Integrated Computational Materials Engineering (2013, methodology): “Development of a computational model involves various steps such as conceptual modeling, mathematical modeling, discretization and algorithm selection, computer programming, numerical solution, solution representation [205].”
• A unified framework and performance benchmark of fourteen multiscale atomistic/continuum coupling methods (2009, methodology): “An important exception to this is the coarse-grain molecular dynamics (CGMD) method of [43].”