Krasnochtchekov Pavel, Averback R S
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
J Chem Phys. 2005 Jan 22;122(4):44319. doi: 10.1063/1.1829973.
Molecular dynamics simulations of vapor-phase nucleation of germanium in an argon atmosphere were performed and a unexpected channel of nucleation was observed. This channel, vapor-induced cluster splitting, is important for more refractory materials since the critical nucleus size can fall below the size of a dimer. As opposed to conventional direct vapor nucleation of the dimer, which occurs by three-body collisions, cluster-splitting nucleation is a second-order reaction. The most important cluster-splitting reaction is the collision of a vapor atom and a trimer that leads to the formation of two dimers. The importance of the cluster-splitting nucleation channel relative to the direct vapor nucleation channel is observed to increase with decreasing vapor density and increasing ratio of vapor to carrier gas atoms.
在氩气气氛中对锗的气相成核进行了分子动力学模拟，并观察到了一个意外的成核通道。这个通道，即气相诱导的团簇分裂，对于更难熔的材料很重要，因为临界核尺寸可能会低于二聚体的尺寸。与通过三体碰撞发生的二聚体的传统直接气相成核相反，团簇分裂成核是二级反应。最重要的团簇分裂反应是一个气相原子与一个三聚体的碰撞，导致形成两个二聚体。观察到团簇分裂成核通道相对于直接气相成核通道的重要性随着气相密度的降低和气相与载气原子比例的增加而增加。
