Rodríguez Schmidt R, Hernández Cifre J G, García de la Torre J
Departamento de Química Física, Facultad de Química, Universidad de Murcia, Spain.
Eur Phys J E Soft Matter. 2012 Dec;35(12):9806. doi: 10.1140/epje/i2012-12130-x. Epub 2012 Dec 14.
The calculation of the translational diffusion coefficient of a single flexible polymer chain in dilute solution can be basically addressed either a) within the Einstein theory (calculating the time autocorrelation function of the macromolecule center of mass), or b) within the Kirkwood and Riseman theory for irreversible processes of macromolecules in solution. The equations of the latter theory can be solved employing different approximations that give rise to different values of the diffusion coefficient. In general, the value of the diffusion coefficient obtained through the different theories and approaches varies slightly depending on polymer features like flexibility. In this paper, we evaluate the most common procedures to compute the diffusion coefficient of flexible macromolecules via computer simulation and the difference between the values obtained.
a）在爱因斯坦理论范围内（计算大分子质心的时间自相关函数），或者b）在柯克伍德和里斯曼理论范围内，该理论用于描述溶液中大分子的不可逆过程。后一种理论的方程可以通过采用不同的近似方法来求解，这些近似方法会导致扩散系数出现不同的值。一般来说，通过不同理论和方法得到的扩散系数值会因聚合物的柔韧性等特征而略有不同。在本文中，我们评估了通过计算机模拟计算柔性大分子扩散系数的最常用方法以及所得值之间的差异。
