Instituto de Químca Física Rocasolano, CSIC, Serrano 119, E-28006 Madrid, Spain.
Soft Matter. 2016 Sep 28;12(36):7551-63. doi: 10.1039/c6sm01400c. Epub 2016 Aug 10.
Template-assisted pattern formation in monolayers of particles with competing short-range attraction and long-range repulsion interactions (SALR) is studied by Monte Carlo simulations in a simple generic model [N. G. Almarza et al., J. Chem. Phys., 2014, 140, 164708]. We focus on densities corresponding to formation of parallel stripes of particles and on monolayers laterally confined between straight parallel walls. We analyze both the morphology of the developed structures and the thermodynamic functions for broad ranges of temperature T and the separation L2 between the walls. At low temperature stripes parallel to the boundaries appear, with some corrugation when the distance between the walls does not match the bulk periodicity of the striped structure. The stripes integrity, however, is rarely broken for any L2. This structural order is lost at T = TK(L2) depending on L2 according to a Kelvin-like equation. Above the Kelvin temperature TK(L2) many topological defects such as breaking or branching of the stripes appear, but a certain anisotropy in the orientation of the stripes persists. Finally, at high temperature and away from the walls, the system behaves as an isotropic fluid of elongated clusters of various lengths and with various numbers of branches. For L2 optimal for the stripe pattern the heat capacity as a function of temperature takes the maximum at T = TK(L2).
利用蒙特卡罗模拟在简单的通用模型中研究了具有竞争短程吸引和长程排斥相互作用 (SALR) 的粒子单层中的模板辅助图案形成[ N. G. Almarza 等人，J. Chem. Phys.，2014，140，164708]。我们专注于对应于平行粒子条纹形成的密度以及在平行直壁之间横向限制的单层。我们分析了在宽温度范围 T 和壁之间的分离 L2 下发展结构的形态和热力学函数。在低温下，与边界平行的条纹出现，当壁之间的距离与条纹结构的体周期性不匹配时，会出现一些波纹。然而，对于任何 L2，条纹的完整性很少被打破。这种结构顺序根据 Kelvin 样方程，根据 L2 在 T = TK(L2) 处丢失。在 Kelvin 温度 TK(L2)以上，会出现许多拓扑缺陷，例如条纹的断裂或分支，但条纹的取向仍存在一定的各向异性。最后，在高温和远离壁的情况下，系统表现为各向异性的伸长簇流体，具有各种长度和分支数。对于最佳的条纹图案 L2，热容随温度的函数在 T = TK(L2) 处取最大值。
