Turci Francesco, Schilling Tanja
Theory of Soft Condensed Matter, Physics and Materials Science Research Unit, Université du Luxembourg, L-1511 Luxembourg, Luxembourg.
J Chem Phys. 2014 Aug 7;141(5):054706. doi: 10.1063/1.4891671.
We discuss the growth process of a crystalline phase out of a metastable over-compressed liquid that is brought into contact with a crystalline substrate. The process is modeled by means of molecular dynamics. The particles interact via the Lennard-Jones potential and their motion is locally thermalized by Langevin dynamics. We characterize the relaxation process of the solid-liquid interface, showing that the growth speed is maximal for liquid densities above the solid coexistence density, and that the structural properties of the interface rapidly converge to equilibrium-like properties. In particular, we show that the off-equilibrium dynamic stiffness can be extracted using capillary wave theory arguments, even if the growth front moves fast compared to the typical diffusion time of the compressed liquid, and that the dynamic stiffness converges to the equilibrium stiffness in times much shorter than the diffusion time.
我们讨论了一种亚稳态过压缩液体与晶体衬底接触时晶相的生长过程。该过程通过分子动力学进行建模。粒子通过 Lennard-Jones 势相互作用，其运动由朗之万动力学进行局部热化。我们对固液界面的弛豫过程进行了表征，表明对于高于固体共存密度的液体密度，生长速度最大，并且界面的结构性质迅速收敛到类似平衡的性质。特别是，我们表明即使生长前沿的移动速度比压缩液体的典型扩散时间快，也可以使用毛细波理论来提取非平衡动态刚度，并且动态刚度在比扩散时间短得多的时间内收敛到平衡刚度。
