Institut für Theoretische Physik and Center for Computational Materials Science, Technische Universität Wien, Wiedner Hauptstraße 8-10, A-1040 Wien, Austria.
J Phys Condens Matter. 2012 Jul 18;24(28):284124. doi: 10.1088/0953-8984/24/28/284124. Epub 2012 Jun 27.
We study the ordered equilibrium structures of patchy particles where the patches are located on the surface of the colloid such that they form a regular tetrahedron. Using optimization techniques based on ideas of evolutionary algorithms we identify possible candidate structures. We retain not only the energetically most favourable lattices but also include a few energetically less favourable particle arrangements (i.e., local minima on the enthalpy landscape). Using suitably developed Monte Carlo based simulation techniques in an NPT ensemble we evaluate the thermodynamic properties of these candidate structures along selected isobars and isotherms and identify thereby the respective ranges of stability. We demonstrate on a quantitative level that the equilibrium structures at a given state point result from a delicate compromise between entropy, energy (i.e., the lattice sum) and packing.
我们研究了在胶体表面上定位的有斑块的粒子的有序平衡结构，使得它们形成一个规则的四面体。我们使用基于进化算法思想的优化技术来确定可能的候选结构。我们不仅保留了能量上最有利的晶格，还包括一些能量上不太有利的粒子排列（即在焓景观上的局部最小值）。我们使用适当开发的基于蒙特卡罗的模拟技术在 NPT 系综中评估这些候选结构在选定的等压线和等温线上的热力学性质，并确定相应的稳定性范围。我们在定量水平上证明了在给定状态点的平衡结构是熵、能量（即晶格和）和包装之间的微妙平衡的结果。
