The effect of non-mesogenic biphenyl impurity on the orientational order parameter of 4-cyano-4'-n-octyl-biphenyl (8CB)

被引：4
作者：
Chakraborty, Saswati [1 ]
Mukhopadhyay, Anuradha [1 ]
机构：
[1] Jadavpur Univ, Dept Phys, Kolkata, India
来源：
PHASE TRANSITIONS | 2009年 / 82卷 / 02期
关键词：
mesogen; mixture; birefringence; polarisability; order parameter; NEMATIC-ISOTROPIC TRANSITIONS; LIQUID-CRYSTALS; PHASE-TRANSITION; DIPOLE-MOMENTS; MOLECULES; PERMITTIVITY; MESOPHASES; SOLVENTS; SOLUTES; MIXTURE;
D O I：
10.1080/01411590802416033
中图分类号：
O7 [晶体学];
学科分类号：
0702 ; 070205 ; 0703 ; 080501 ;
摘要：
The role of non-mesogenic impurities on a mesogen and the consequent alteration of mesogenic properties have always been of great interest in the tailoring of mesogenic behaviour. In the present work the effect of rigid, non-polar, nonmesogenic solute 'biphenyl' on the optical properties of the mesogen 4-cyano-4'-n-octyl-biphenyl (8CB) has been reported. The phase transitions and thermal variations of the refractive index, polarisability and order parameter P2 of the 8CB-biphenyl systems of various concentrations have been investigated using a He-Ne laser beam. The results have been compared with P2 of pure 8CB. It has been observed that biphenyl lowers both smecticA-nematic and nematic-isotropic transition temperatures by an amount that depends on impurity concentration.
引用
收藏
页码：115 / 122
页数：8
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