论文标题
动力胶体悬浮液中竞争晶体多晶型成核和生长的动力学相图
Kinetic phase diagram for nucleation and growth of competing crystal polymorphs in charged colloidal suspensions
论文作者
论文摘要
我们确定了带电胶体悬浮液中晶相的成核和生长的完整动力学相图。我们计算以面部为中心的立方（FCC）和以身体为中心的立方（BCC）晶体相的成核屏障高度，用于在广泛的模拟中使用播种方法使用播种方法来改变筛选长度和过饱和。使用经典的成核理论，我们确定整个亚稳态流体区域的晶体多晶型物具有最低的成核屏障。出人意料的是，我们发现一个接近三重点的机制，即使FCC是稳定相，由于较低的成核屏障，亚稳态BCC可以形成。为了获得更高的过饱和，我们发现屏障高度的差异降低，并且观察到六角形封闭式包装（HCP），FCC和BCC结构的混合物在结晶种子的生长以及自发形成的晶体中的混合物。
We determine the full kinetic phase diagram for nucleation and growth of crystal phases in a suspension of charged colloids. We calculate nucleation barrier heights for face-centered cubic (fcc) and body-centered cubic (bcc) crystal phases for varying screening lengths and supersaturations using the seeding approach in extensive simulations. Using classical nucleation theory, we determine for the entire metastable fluid region the crystal polymorph with the lowest nucleation barrier. Surprisingly, we find a regime close to the triple point where metastable bcc can form due to a lower nucleation barrier, even though fcc is the stable phase. For higher supersaturation, we find that the difference in barrier heights decreases and we observe a mix of hexagonal close-packed (hcp), fcc and bcc structures in the growth of crystalline seeds as well as in spontaneously formed crystals.
