论文标题
磁场对超par磁单体的类似聚合物上胶质样结构的构象的影响
The impact of magnetic field on the conformations of supracolloidal polymer-like structures with super-paramagnetic monomers
论文作者
论文摘要
我们研究了具有超par磁单体的磁性上二元聚合物（MFS）的特性，它们之间具有和没有范德华（Van der Waals）（VDW）的吸引力。我们采用分子动力学（MD）模拟来阐明交联机制对MFS对应用外部均匀磁场的结构和磁反应的影响。我们考虑了两个模型：普通的交联，这会导致柔性骨干。并约束交联，这为弯曲提供了明显的僵硬。我们发现，对于普通的交联，即使中央吸引力的略有增加也会导致MF构型崩溃。最初表现出球形对称性的结构演变成圆柱对称的结构，具有增长的磁场强度。普通的交联还允许构象的双重性。交联受限的MF倾向于在场中解散。在这两种交联场景中，中央吸引力都能够阻止MF的低场磁反应，尽管在高田区域中，明显交联的MF的双重性也表现出来。
We investigate the properties of magnetic supracolliodal polymers -- magnetic filaments (MFs) -- with super-paramagnetic monomers, with and without Van der Waals (VdW) attraction between them. We employ molecular dynamics (MD) simulations to elucidate the impact of crosslinking mechanism on the structural and magnetic response of MFs to an applied external homogeneous magnetic field. We consider two models: plain crosslinking, which results in a flexible backbone; and constrained crosslinking, which provides significant stiffens against bending. We find that for plain crosslinking, even a slight increase of the central attraction leads to collapsed MF conformations. Structures that initially exhibit spherical symmetry evolve into cylindrically symmetric ones, with growing magnetic field strength. Plain crosslinking also allows for conformational bistability. MFs with constrained crosslinking tend to, instead, unravel in field. In both crosslinking scenarios, central attraction is able to hinder low-field magnetic response of MFs, albeit the bistability of plainly crosslinked MFs manifests itself also in the high-field region.
