[1]王焕景,刘红.十字形液晶分子系统各向同性相至双轴向列相的相变[J].南京师大学报(自然科学版),2011,34(02):39-44.
　Wang Huanjing,Liu Hong.Phase Transitions From Isotropic to Biaxial Phase of Cross-Like Nematic Liquid Crystal Molecules[J].Journal of Nanjing Normal University(Natural Science Edition),2011,34(02):39-44.
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十字形液晶分子系统各向同性相至双轴向列相的相变()
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《南京师大学报（自然科学版）》[ISSN:1001-4616/CN:32-1239/N]

卷:
第34卷
期数:
2011年02期
页码:
39-44
栏目:
物理学
出版日期:
2011-06-20

文章信息/Info

Title:
Phase Transitions From Isotropic to Biaxial Phase of Cross-Like Nematic Liquid Crystal Molecules
作者:
王焕景;  刘红
南京师范大学物理科学与技术学院, 江苏南京210046
Author(s):
Wang Huanjing; Liu Hong
School of Physics and Technology,Nanjing Normal University,Nanjing 210046,China
关键词:
双轴向列相液晶;  相变;  分子相互作用
Keywords:
b iax ia l nem a tic liqu id cry sta ; l phase transition;  m olecu lar interaction
分类号:
O753.2
摘要:
本文考虑十字形液晶分子组成的系统,假设分子间相互作用为棒与棒相互作用的叠加,且相互作用强度系数彼此独立.利用平均场理论,得到系统在温度和分子结构参数平面内的3类相图:第一类相图中只有一个直接由各向同性相进入双轴相的Landau点,相变为二级相变.第二类相图中Landau点扩展为Landau曲线,为一级相变.第三类相图中,Landau点同样扩展为Landau曲线,但范围缩小.上述3类相图表明,相变类型,Landau曲线的出现与分子间相互作用强度系数的选取有关.
Abstract:
A system com po sed o f cro ss- like nema tic liqu id cry sta lm o lecules is cons idered. Suppo se them o lecular interac tion is the superposition o f interactions am ongm o lecular rods, and the streng ths of inte ractions are independent. W ithin the m ean field theory, three types o f phase d iag ram s in the p lane o f temperature and them o lecular structure param eters are obta ined. In the first type of phase diag ram, there appears only one Landau po int a tw hich system enter d irec tly from isotropic to b iax ial phase by second orde r phase transition. In the second type, Landau po int becom es a Landau curv ew here sy stem ente rs from iso trop ic to biax ia l phase by first order phase trans ition. In the th ird type, the Landau curv e still ex ists, bu tw ith in a sm alle r range. The above phase d iagram s show tha t the types o f phase transitions and occurrence o f Landau curve depend on the va lues of m olecular interaction streng ths

参考文献/References:

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[ 2]  A chary a B R, Pr imak A, Kum ar S. B iax ia l nem atic phase in bent-core therm otropicm esogens[ J]. Phys Rev Lett, 2004, 92 ( 14): 45506- 1-45506- 4.
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[ 5]  G ram sbe rgen E F, Long a I, JeuW H de. Landau theory of the nem atic- isotropic phase transition[ J]. Phy s Rev Lett, 1986, 135( 4) : 195-257.
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[ 7]  BatesM A, Luckhurst G R. B iax ial nem a tic phases and V- shaped m o lecules: aM onte Car lo sim ulation study[ J] . Phys Rev E, 2005, 72( 5): 051702- 1-051702- 15.
[ 8] 骆文玲, 刘红. Y 形分子系统相变的蒙特卡罗模拟[ J]. 南京师大学报: 自然科学版, 2010, 33( 3) : 26-31.
[ 9] Sonnet A M, V irga E G, Durand G E. D ie lec tric shape d ispersion and biax ia l transitions in nem atic liqu id crysta ls[ J]. Phy sRev E, 2003, 67( 6): 061701- 1-061701- 8.

相似文献/References:

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　Luo Wenling,Liu Hong.Monte Carlo Simulation of Biaxial Phase Transitions in Y-Shaped Molecular System[J].Journal of Nanjing Normal University(Natural Science Edition),2010,33(02):26.
[2]章其林,刘红.双轴向列相液晶在外场中的周期性形变[J].南京师大学报(自然科学版),2007,30(02):47.
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[3]翟雪雅,刘红.由弹性键连接的V形分子双轴向列相液晶的相变[J].南京师大学报(自然科学版),2010,33(02):31.
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备注/Memo

备注/Memo:
基金项目: 江苏省普通高校自然科学研究项目( 07JKD140095 ). 通讯联系人: 刘?? 红, 博士, 教授, 研究方向: 液晶物理理论(相变和弹性理论) . E-m ail:liuhong@ njnu. edu. cn
更新日期/Last Update: 2011-06-15