Xu J, Veracini C A, Dong Ronald Y
Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Jan;73(1 Pt 1):011705. doi: 10.1103/PhysRevE.73.011705. Epub 2006 Jan 12.
The results of studying angular dependent spectral parameters in a magnetic field are reported in the chiral smectic C phases of a smectogen 1-methylheptyl -(4-n-decyloxybenzoyloxy)-biphenyl-4-carboxylate. Our data provide direct evidence of a phase transition between two ferrielectric phases in this compound, viz. three-layer (SmC*(FiI)) and four-layer (SmC*(FiII)) superlattices. Simulation of spectral patterns of the methyl (C10) deuterons obtained after an aligned sample is rotated by 90 degrees in the magnetic field rules out the "clock model" for the three-layer and four-layer structures in these ferriphases. Instead, our data obtained under a magnetic field (9.4 T) seem to favor an "asymmetric clock model" for the interlayer packing. Interlayer jump rate is also obtained from the simulation of angular dependent spectra in these ferrielectric phases, and compared with those in the antiferroelectric SmC*(A) phase.
报道了在磁场中研究近晶型1-甲基庚基-（4-正癸氧基苯甲酰氧基）-联苯-4-羧酸酯手性近晶C相中的角度相关光谱参数的结果。我们的数据为该化合物中两个铁电相之间的相变提供了直接证据，即三层（SmC*(FiI)）和四层（SmC*(FiII)）超晶格。在磁场中将取向样品旋转90度后获得的甲基（C10）氘核光谱模式的模拟排除了这些铁电相中三层和四层结构的“时钟模型”。相反，我们在磁场（9.4 T）下获得的数据似乎支持层间堆积的“不对称时钟模型”。还从这些铁电相中的角度相关光谱模拟中获得了层间跳跃率，并与反铁电SmC*(A)相中的层间跳跃率进行了比较。
