Magnetic alignment study of rare-earth-containing liquid crystals.
Magnetic alignment study of rare-earth-containing liquid crystals.
复制标题
含稀土液晶的磁取向研究。
DOI：
10.1021/jp0771724
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
K. Binnemans
中科院分区：
文献类型：
--
作者：
Y. Galyametdinov;W. Haase;B. Goderis;D. Moors;K. Driesen;R. Van Deun;K. Binnemans
[Ln（LH）3（DOS）3]型液晶稀土配合物-其中Ln是Tb、Dy、Ho、Er、Tm或Yb; LH是Schiff碱N-十八烷基-4-十四烷氧基水杨醛亚胺; DOS是十二烷基硫酸盐-表现出近晶A相。由于存在具有大的磁各向异性的稀土离子，这些液晶的近晶A相可以比常规液晶的近晶A相更容易在外部磁场中取向。[Ln（LH）3（DOS）3]配合物的磁各向异性通过使用法拉第天平测量磁化率的温度依赖性来确定。镝（III）复合物的磁各向异性的最高值。利用时间分辨同步辐射小角X射线散射实验研究了这些液晶的磁性取向。根据磁各向异性的符号，液晶分子的指向矢平行或垂直于磁场线排列。一个正值的磁各向异性（和平行排列）被发现的铥（III）和镱（III）的配合物，而观察到的铽（III）和镝（III）的配合物的磁各向异性（和垂直排列）的负值。
The liquid-crystalline rare-earth complexes of the type [Ln(LH)3(DOS)3]-where Ln is Tb, Dy, Ho, Er, Tm, or Yb; LH is the Schiff base N-octadecyl-4-tetradecyloxysalicylaldimine; and DOS is dodecylsulfate-exhibit a smectic A phase. Because of the presence of rare-earth ions with a large magnetic anisotropy, the smectic A phase of these liquid crystals can be easier aligned in an external magnetic field than smectic A phases of conventional liquid crystals. The magnetic anisotropy of the [Ln(LH)3(DOS)3] complexes was determined by measurement of the temperature-dependence of the magnetic susceptibility using a Faraday balance. The highest value for the magnetic anisotropy was found for the dysprosium(III) complex. The magnetic alignment of these liquid crystals was studied by time-resolved synchrotron small-angle X-ray scattering experiments. Depending on the sign of the magnetic anisotropy, the director of the liquid-crystalline molecules was aligned parallel or perpendicular to the magnetic field lines. A positive value of the magnetic anisotropy (and parallel alignment) was found for the thulium(III) and the ytterbium(III) complexes, whereas a negative value of the magnetic anisotropy (and perpendicular alignment) was observed for the terbium(III) and dysprosium(III) complexes.
DOI：
--
发表时间：
2003
期刊：
影响因子：
--
作者：
T.Nishigaki et al.;S.Itoh.et al.
通讯作者：
S.Itoh.et al.