Despa Florin, Wales David J, Berry R Stephen
Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA.
J Chem Phys. 2005 Jan 8;122(2):024103. doi: 10.1063/1.1829633.
Recent studies have identified several motifs for potential energy surfaces corresponding to distinct dynamic and thermodynamic properties. The corresponding disconnectivity graphs were identified as "palm tree," "willow tree," and "banyan tree" patterns. In the present contribution we present a quantitative analysis of the relation between the topography and dynamics for each of these motifs. For the palm tree and willow tree forms we find that the arrangement of the stationary points in the monotonic sequences with respect to the global minimum is the most important factor in establishing the kinetic properties. However, the results are somewhat different for motifs involving a rough surface with several deep basins (banyan tree motif), with large barriers relative to the energy differences between minima. Here it is the size of the barrier for escape from the region relative to the barriers at the bottom that is most important. The present results may be helpful in distinguishing between the dynamics of "structure seeking" and "glass forming" systems.
最近的研究已经确定了几个对应于不同动力学和热力学性质的势能面基序。相应的不连通图被识别为“棕榈树”“柳树”和“榕树”模式。在本论文中，我们对这些基序中每一个的地形与动力学之间的关系进行了定量分析。对于棕榈树和柳树形式，我们发现相对于全局最小值，单调序列中驻点的排列是确定动力学性质的最重要因素。然而，对于涉及具有多个深盆的粗糙表面的基序（榕树基序），其结果有所不同，相对于最小值之间的能量差而言，具有较大的势垒。在这里，相对于底部的势垒，从该区域逃逸的势垒大小是最重要的。目前的结果可能有助于区分“结构寻找”和“玻璃形成”系统的动力学。
