Design of photonic liquid crystal materials: synthesis and evaluation of new chiral thioindigo dopants designed to photomodulate the spontaneous polarization of ferroelectric liquid crystals
Design of photonic liquid crystal materials: synthesis and evaluation of new chiral thioindigo dopants designed to photomodulate the spontaneous polarization of ferroelectric liquid crystals
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DOI：
10.1039/a903052b
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发表时间：
1999
影响因子：
--
通讯作者：
L. Dinescu;K. Maly;R. Lemieux
中科院分区：
文献类型：
--
作者：
L. Dinescu;K. Maly;R. Lemieux
光致变色掺杂剂（R，R）-6，6 ′-双（2-辛氧基）-5，5 ′-二硝基硫靛和（R，R）-5，5 ′-二氯-6，6 ′-双（2-辛氧基）硫靛分别在λ=514和532 nm处诱导铁电SC * 液晶相的辐射，引起自发极化（PS）增加1.4 ~ 4.0倍。这种增加在PS实现没有伴随的SC * 相的不稳定，并且是一致的，作为反式-顺式光异构化的结果的硫靛核心的横向偶极矩的增加。硫靛核对PS的贡献是通过与手性侧链的立体极性偶联实现的，这是通过硝基和氯取代基的存在而增强的。
Irradiation of a ferroelectric S C * liquid crystal phase induced by the photochromic dopants (R,R)-6,6′-bis(2-octyloxy)-5,5′-dinitrothioindigo and (R,R)-5,5′-dichloro-6,6′-bis(2-octyloxy)thioindigo at λ=514 and 532 nm, respectively, causes an increase in spontaneous polarization (P S ) by a factor ranging from 1.4 to 4.0. This increase in P S is achieved without concomitant destabilization of the S C * phase, and is consistent with an increase in transverse dipole moment of the thioindigo core as a result of trans-cis photoisomerization. The contribution of the thioindigo core towards P S is achieved through stereo-polar coupling with the chiral side-chains, which is enhanced by the presence of the nitro and chloro substituents.