Field response and switching times in biaxial nematics.
Field response and switching times in biaxial nematics.
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DOI：
10.1063/1.2815804
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发表时间：
2008-01
期刊：
影响因子：
--
通讯作者：
R. Berardi;L. Muccioli;C. Zannoni
中科院分区：
文献类型：
--
作者：
R. Berardi;L. Muccioli;C. Zannoni
我们通过虚拟分子动力学计算机实验研究了体相双轴向列相对外场的响应，特别是在Pi2场开关下这些新材料的典型代表--主矢向轴和次矢向轴的相对重定向速度。我们使用四元数和适当的时间可逆辛积分器对双轴Gay-Berne粒子的运动方程进行了模拟建立和积分。我们发现，次轴的转换比主轴的转换快一个数量级，在高于一定强度的场下，局域的重组暂时破坏了向列相和双向有序，而不是集体协调的重新定向。
We study by means of virtual molecular dynamics computer experiments the response of a bulk biaxial nematic to an applied external field and, in particular, the relative speed of reorientation of the principal director axis and of the secondary one, typical of these new materials, upon a pi2 field switch. We perform the simulations setting up and integrating the equations of motion for biaxial Gay-Berne particles using quaternions and a suitable time reversible symplectic integrator. We find that switching of the secondary axis is up to an order of magnitude faster than that of the principal axis, and that under fields above a certain strength a reorganization of local domains, temporarily disrupting the nematic and biaxial ordering, rather than a collective concerted reorientation occurs.