Fernandes P, Barois P, Grelet E, Nallet F, Goodby J W, Hird M, Micha J-S
Centre de Recherche Paul-Pascal-CNRS, Université Bordeaux 1, Avenue A. Schweitzer, 33600, Pessac, France.
Eur Phys J E Soft Matter. 2006 May;20(1):81-7. doi: 10.1140/epje/i2006-10006-4. Epub 2006 May 17.
We report X-ray resonant scattering experiments performed on the prototype liquid-crystalline compound MHPOBC doped with a chemical probe containing a resonant atom (selenium). We determined directly for the first time the microscopic 3- and 4-layer structure of the ferrielectric subphases (SmC(FI1)* and SmC(FI2)) present in MHPOBC. Despite the low fraction of the selenium probe, the resonant signal is strong enough to allow an unambiguous determination of the basic structure of the ferrielectric subphases. These experiments demonstrate that the resonant scattering technique can be extended to liquid crystalline materials without resonant element and may stimulate new studies. A non-resonant Bragg reflection was also found in the SmC(FI1) phase in pure MHPOBC, consistent with the 3-layer distorted model, but never detected before.
我们报告了对掺杂有含共振原子（硒）的化学探针的原型液晶化合物MHPOBC进行的X射线共振散射实验。我们首次直接确定了MHPOBC中存在的铁电亚相（SmC(FI1)和SmC(FI2)）的微观三层和四层结构。尽管硒探针的比例很低，但共振信号足够强，能够明确确定铁电亚相的基本结构。这些实验表明，共振散射技术可以扩展到没有共振元素的液晶材料，并可能激发新的研究。在纯MHPOBC的SmC(FI1)*相中还发现了非共振布拉格反射，这与三层扭曲模型一致，但此前从未检测到。
