Insights into Biaxial Ordering of Bent-Core Nematics: X-Ray Diffraction Evidence

被引:8
作者
Vita, F. [1 ]
Tauscher, T. [2 ]
Speetjens, F. [2 ]
Ferrero, C. [3 ]
Samulski, E. T. [4 ]
Scharrer, E. [2 ]
Francescangeli, O. [1 ]
机构
[1] Univ Politecn Marche, Dipartimento SIMAU & CNISM, I-60131 Ancona, Italy
[2] Univ Puget Sound, Dept Chem, Tacoma, WA 98416 USA
[3] European Synchrotron Radiat Facil, F-38043 Grenoble, France
[4] Univ N Carolina, Dept Chem, Chapel Hill, NC USA
基金
美国国家科学基金会;
关键词
bent-core mesogens; biaxiality; X-ray diffraction; cybotaxis; LIQUID-CRYSTALS; PHASE; MESOGENS; MESOPHASES; SHAPE; UNIT;
D O I
10.1080/15421406.2015.1030232
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Recently we have reported the first X-ray diffraction evidence of biaxial order in the fluid cybotactic nematic phase of a pair of trimethylated bent-core mesogens. This evidence is based on the splitting of the wide-angle diffuse scattering in the plane normal to the nematic director. The additional experimental data presented here provide further insights into this unprecedented behavior observed over the entire nematic phase. Although we could not determine the spatial extent of biaxial order-intracluster or intercluster-our observations reveal an enhanced biaxial orientational correlation in the transverse molecular packing, possibly reflecting stronger anisotropic interactions between nearest-neighbor mesogens.
引用
收藏
页码:171 / 179
页数:9
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