Center for Simulational Physics, The University of Georgia, Athens, Georgia 30602, USA.
J Chem Phys. 2013 Feb 21;138(7):074905. doi: 10.1063/1.4790615.
We systematically investigate how the range of interaction between non-bonded monomers influences the formation of structural phases of elastic, flexible polymers. Massively parallel replica-exchange simulations of a generic, coarse-grained model, performed partly on graphics processing units and in multiple-gaussian modified ensembles, pave the way for the construction of the structural phase diagram, parametrized by interaction range and temperature. Conformational transitions between gas-like, liquid, and diverse solid (pseudo) phases are identified by microcanonical statistical inflection-point analysis. We find evidence for finite-size effects that cause the crossover of "collapse" and "freezing" transitions for very short interaction ranges.
我们系统地研究了非键单体之间的相互作用范围如何影响弹性、柔性聚合物结构相的形成。通过在图形处理单元上部分执行的、基于多高斯修正系综的通用粗粒化模型的大规模并行 replica-exchange 模拟,为构建结构相图铺平了道路,该相图由相互作用范围和温度来参数化。通过微正则统计拐点分析,识别出了气体状、液体状和不同固体(拟)相之间的构象转变。我们发现了有限尺寸效应的证据,这些效应导致了非常短的相互作用范围下“塌陷”和“冻结”转变的交叉。