Coarse-graining molecular dynamics models using an extended Galerkin projection

Xiantao Li

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arXiv · 1210.4153

Coarse-graining molecular dynamics models using an extended Galerkin projection

Xiantao Li

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Abstract

We present a new framework for coarse-graining molecular dynamics models for crystalline solids. The reduction method is based on a Galerkin projection to a subspace, whose dimension is much smaller than that of the full atomistic model. The subspace is expanded by adding more coarse-grain variables near the interface between lattice defects and the surrounding regions. This effectively minimizes reflection of phonons at the interface. In this approach, there is no need to pre-compute the memory function in the generalized Langevin equations, a typical model of interface conditions. Moreover, the variational formulation preserves the stability of mechanical equilibria.

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Xiantao Li. 2012-10-16. Coarse-graining molecular dynamics models using an extended Galerkin projection. https://arxiv.org/abs/1210.4153

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