Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
Annu Rev Chem Biomol Eng. 2012;3:157-82. doi: 10.1146/annurev-chembioeng-062011-081029. Epub 2012 Mar 9.
We review the molecular principles underlying the homogeneous nucleation of a crystal phase from the melt phase, as elucidated by molecular simulation methods. Classical nucleation theory serves as the starting point for describing the nature of nucleation processes, but it does not derive from molecular principles itself. Density functional theory and molecular simulations offer tools for delving into the molecular origins of nucleation. Here, we emphasize the rapid development of molecular simulation methodologies for studying crystal nucleation from the melt. These methodologies are broadly categorized as free energy sampling methods, dynamical or mean first-passage time methods, and composite approaches that take advantage of both. The crucial selection of order parameters to distinguish the crystal phase from the liquid phase and important features of the reaction coordinate are emphasized. The system size dependence of the nucleation free energy barrier is also examined.
我们回顾了通过分子模拟方法阐明的从熔体相中均相成核晶体相的分子原理。经典成核理论是描述成核过程本质的起点，但它本身并非源自分子原理。密度泛函理论和分子模拟为深入研究成核的分子起源提供了工具。在这里，我们强调了用于研究熔体中晶体成核的分子模拟方法的快速发展。这些方法大致可分为自由能采样方法、动力学或平均首次通过时间方法，以及利用两者的组合方法。强调了选择区分晶体相和液相的序参数的关键以及反应坐标的重要特征。还研究了成核自由能势垒的系统尺寸依赖性。
