Gruhn-Hess两体势修正模型向列相液晶微滴的Monte Carlo模拟  

Monte Carlo Simulation of Nematic Droplets with Modified Gruhn-Hess Pair Potential

作　　者：张艳君[1] 王超[1] 叶文江[1] 张志东[1] 

机构地区：[1]河北工业大学理学院,天津300130

出　　处：《计算物理》2013年第2期244-250,共7页Chinese Journal of Computational Physics

基　　金：国家自然科学基金(11147103);河北省高等学校科学技术研究指导项目(Z2011133;Z2012067;Z2012061);河北省自然科学基金(A2010000004)资助项目

摘　　要：基于Gruhn-Hess两体势修正模型,用Monte Carlo方法模拟向列相液晶微滴.Gruhn-Hess两体势是空间各向异性的,修正模型的势参数依赖于液晶的弹性常数K11、K22、K33及表面弹性常数K13.假设向列相液晶微滴具有自由表面,在低温下计算分子二阶序参数和切向内禀强度在微滴内不同区域的变化,并与Gruhn-Hess两体势模型一作对比分析.结果表明:附加K13项的修正模型在微滴表面产生内禀锚定,其大小决定了内禀易取向方向及内禀锚定强度的大小,且内禀强度的大小与K33/K11值有关;空间不完整的向列相液晶微滴由内层到外层有序度逐渐降低.Nematic droplets are studied with Monte Carlo simulations with a modified Gruhn-Hess pair potential. The potential is spatially anisotropic and potential parameters are related to elastic constants K11 ,K22 ,K33 and surface-like elastic constant K13. It is assumed that nematic droplet surface is a free surface. Second order parameters and introrse intensity, which describes quantitatively intrinsic anchoring induced by surface at low temperatures, are calculated with a modified Gruhn-Hess pair potential and are compared with those in Gruhn-Hess model I. It is shown that the modified model with K13 induces intrinsic anchoring near droplet surface, orientation and intrinsic anchoring strength depend strongly on K13, and introrse intensity is related to K33/K11. Order degree of nematic droplet is lower from inner shell to outer shell due to incomplete anisotropic nematic-nematic interactions.

关 键 词：向列相液晶微滴 Gruhn-Hess两体势 MonteCarlo方法 修正模型 内禀锚定 

分 类 号：O753[理学—晶体学]