Mu Yan, Houk Andrew, Song Xueyu
Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
J Phys Chem B. 2005 Apr 14;109(14):6500-4. doi: 10.1021/jp046289e.
We present a reliable method to define the interfacial particles for determining the crystal-melt interface position, which is the key step for the crystal-melt interfacial free energy calculations using capillary wave approach. Using this method, we have calculated the free energies gamma of the fcc crystal-melt interfaces for the hard-sphere system as a function of crystal orientations by examining the height fluctuations of the interface using Monte Carlo simulations. We find that the average interfacial free energy gamma(0) = 0.62 +/- 0.02k(B)T/sigma(2) and the anisotropy of the interfacial free energies are weak, gamma(100) = 0.64 +/- 0.02, gamma(110) = 0.62 +/- 0.02, gamma(111) = 0.61 +/- 0.02k(B)T/sigma(2). The results are in good agreement with previous simulation results based on the calculations of the reversible work required to create the interfaces (Davidchack and Laird, Phys. Rev. Lett. 2000, 85, 4571). In addition, our results indicate gamma(100) > gamma(110) > gamma(111) for the hard-sphere system, similar to the results of the Lennard-Jones system.
我们提出了一种可靠的方法来定义用于确定晶体 - 熔体界面位置的界面粒子，这是使用毛细管波方法计算晶体 - 熔体界面自由能的关键步骤。使用这种方法，我们通过蒙特卡罗模拟检查界面的高度波动，计算了硬球系统中面心立方晶体 - 熔体界面的自由能γ作为晶体取向的函数。我们发现平均界面自由能γ(0)= 0.62±0.02k(B)T/σ(2)，并且界面自由能的各向异性较弱，γ(100)= 0.64±0.02，γ(110)= 0.62±0.02，γ(111)= 0.61±0.02k(B)T/σ(2)。这些结果与基于创建界面所需的可逆功计算的先前模拟结果（Davidchack和Laird，《物理评论快报》，2000年，85卷，4571页）非常吻合。此外，我们的结果表明，对于硬球系统，γ(100)>γ(110)>γ(111)，这与 Lennard-Jones 系统的结果类似。
