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arXiv · 1310.3704

Nonlinear hydrodynamic theory of crystallization

Gyula I. Tóth·László Gránásy·György Tegze
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Abstract

We present an isothermal fluctuating nonlinear hydrodynamic theory of crystallization in molecular liquids. A dynamic coarse-graining technique is used to derive the velocity field, a phenomenology, which allows a direct coupling between the free energy functional of the classical Density Functional Theory and the Navier-Stokes equation. Contrary to the Ginzburg-Landau type amplitude theories, the dynamic response to elastic deformations is described by parameter-free kinetic equations. Employing our approach to the free energy functional of the Phase-Field Crystal model, we recover the classical spectrum for the phonons and the steady-state growth fronts. The capillary wave spectrum of the equilibrium crystal-liquid interface is in a good qualitative agreement with the molecular dynamics simulations.

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Gyula I. Tóth, László Gránásy, György Tegze. 2013-10-14. Nonlinear hydrodynamic theory of crystallization. https://arxiv.org/abs/1310.3704

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