Institut für Computerphysik, Universität Stuttgart, D-70569 Stuttgart, Germany.
J Chem Phys. 2013 Jul 28;139(4):044904. doi: 10.1063/1.4815915.
We study the equilibrium morphologies of a single supramolecular magnetic filament in a three-dimensional system as a function of the effective strength of the magnetic dipolar interactions. The study is performed by means of Langevin dynamics simulations with a bead-spring chain model of freely rotating dipoles. We demonstrate the existence of three structural regimes as the value of the dipolar coupling parameter is increased: a coil compaction regime, a coil expansion regime, and a closed chain regime in which the structures tend progressively to an ideal ring configuration. We discuss the governing effects of each regime, the structural transition between open and closed morphologies, and the reasons why we see no multiloop configurations that have been observed in two-dimensional systems under similar conditions.
我们研究了在三维系统中单个超分子磁丝的平衡形态作为磁偶极力有效强度的函数。这项研究是通过带有自由旋转偶极子的珠-簧链模型的朗之万动力学模拟来进行的。我们证明了随着偶极力耦合参数值的增加存在三个结构区域：一个是线圈紧缩区域，一个是线圈扩展区域，另一个是在这个区域中结构逐渐趋向于理想的环形配置。我们讨论了每个区域的控制效果、开放和封闭形态之间的结构转变，以及为什么我们在类似条件下的二维系统中没有观察到多环结构的原因。
