研究了紫外光照和温度对偶氮弯曲液晶极化电流的影响.在365 nm紫外光照下,这种偶氮化合物的极化强度随紫外光照时间增加而变化直至为零；当温度从150℃升高到175 ℃时,弯曲液晶的极化电流随温度线性降低,用Landau-de Gennes理论解释了这一现象.其极化情况随紫外光照和温度而变化的实验规律表明:在紫外光照下偶氮弯曲液晶发生了光致异构化、光裂解和热裂解作用.
By triangular wave method,the effects of ultraviolet irradiation and temperature on the polarization of a bent-core liquid crystal containing azobenzene were studied.Under the 365 nm ultraviolet irradiation,the switching currents were observed to change with the time of ultraviolet irradiation until they diminished.As the temperature increases from 150 ℃ to 175 ℃,the switching currents of the bent-core liquid crystal were observed to decrease linearly with temperature.The unusual temperaturedependent polarization was discussed in the light of Landau-de Gennes theory.The results demonstrated that photoisomerization,photolysis and thermolysis may take place in the bent-core liquid crystal containing azobenzene.
参考文献
| [1] | Niori T,Sekine T,Watanabe J W.Distinct ferroelectric smectic liquid crystals consisting of banana shaped achiral molecules[J].J.Mater.Chem.,1996,6:1231-1233. |
| [2] | Prasad V,Kang S W,Kumar S.Novel examples of achiral bent-core azo compounds exhibiting B1 and anticlinicantiferroelectric B2 mesophases[J].J.Mater.Chem.,2003,13:1259-1264. |
| [3] | Huang Y M,Chen L L,Zhou F F,et al. New Trends in Fluid Mechanics Research[M].Beijing:Tsinghua University Press & Springer,2007:61-65. |
| [4] | Chen L L,Tang Z K.Electronic structure and electron transition of banana-shaped liquid crystals[J].Chinese Journal of Liquid Crystals and Displays(液晶与显示),2009,24(4):478-481 (in Chinese). |
| [5] | Wang P,Ming H,Liang Z,et al.Photoinduced birefringence and optical storage in azobenzene side-chain polymer liquid crystal film[J].Chinese Journal of Quantum Electronics(量子电子学报),2002,19(4):358-362 (in Chinese). |
| [6] | Selvanathan S,Peters M V,Schwarz J,et al.Formation and manipulation of discrete supramolecular azobenzene assemblies[J].Appl.Phys.A,2008,93:247-252. |
| [7] | Comstock M J,Levy N,Kirakosian A,et al. Reversible photomechanical switching of individual engineered molecules at a metallic surface[J].Phys.Rev.Lett.,2007,99:038301. |
| [8] | Huang Y M,Zhai B G,Zhou F F.Effects of photo-irradiation on the optical properties and electronic structures of an azo-containing bent-core liquid crystal[J].Molecular Crystals and Liquid Crystals,2009,510:34-38. |
| [9] | Budyka M F,Kantor M M.Thermolysis of azobenzene[J].Russian Chemical Bulletin,1993,42(9):1495-1497. |
| [10] | Neyts K,Beunis F.Ion transport and switching currents in smectic liquid crystal devices[J].Ferroelectrics,2006,344:255-266. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%