Institute of Theoretical Physics, Heinrich Heine University of Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany.
J Phys Condens Matter. 2010 Mar 17;22(10):104107. doi: 10.1088/0953-8984/22/10/104107. Epub 2010 Feb 23.
We investigate the stable crystalline configurations of a nematic liquid crystal made of soft parallel ellipsoidal particles interacting via a repulsive, anisotropic Gaussian potential. For this purpose, we use genetic algorithms (GA) in order to predict all relevant and possible solid phase candidates into which this fluid can freeze. Subsequently we present and discuss the emerging novel structures and the resulting zero-temperature phase diagram of this system. The latter features a variety of crystalline arrangements, in which the elongated Gaussian particles in general do not align with any one of the high-symmetry crystallographic directions, a compromise arising from the interplay and competition between anisotropic repulsions and crystal ordering. Only at very strong degrees of elongation does a tendency of the Gaussian nematics to align with the longest axis of the elementary unit cell emerge.
我们研究了由软平行椭球粒子通过排斥各向异性高斯势相互作用形成的向列液晶的稳定晶态构型。为此，我们使用遗传算法（GA）来预测这种流体可能冻结的所有相关和可能的固相候选物。随后，我们展示并讨论了该系统中出现的新颖结构和相应的零温相图。后者具有多种晶体排列方式，其中，一般来说，拉长的高斯粒子不会与任何一个高对称晶体学方向对齐，这是由于各向异性排斥和晶体有序之间的相互作用和竞争而产生的折衷。只有在非常强的伸长程度下，高斯向列才有倾向与基本单胞的最长轴对齐。
