Structure formation in columnar mineral liquid crystals in confinement (D06)

限制中柱状矿物液晶的结构形成（D06）

• 批准号: 143955405
• 金额: --
• 依托单位: Vant Hoff Laboratory for Physical and Colloid Chemistry
• 依托单位国家: 德国
• 项目类别: CRC/Transregios
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/143955405?language=en
• 关键词: Structure; formation; columnar; mineral; liquid

Following up on our research, we want to study effects of confinement on liquid-crystal phases of anisometric colloids. Since this also requires the use of optical techniques, we shift our emphasis from boardlike Goethite to platelike Gibbsite particles. These hexagons can be prepared with optically accessible diameters using seeded growth and in principle can be made fluorescent. We have previously found that the native platelets form a nematic phase and 2 types of columnar phases: both a hexagonal phase with long-range 2D ordering and a hexaticlike phase which is ordered orientationally but lacks true long-range positional order. Since this is intrinsically related to the possibility of fluctuations of the columns and the occurrence of defects, one of our research goals is to study how the hexagonal and hexatic order is affected by confinement and anchoring in different geometries (gaps, wedges). We also intend to use patterned surfaces to study the packing of columns in wedges. An important technique to study these confined systems is microradian x-ray diffraction, but also newly developed synchrotron techniques like x-ray microscopy could be interesting. These measurements will be complemented by (polarization and/or confocal) light microscopy to address the local (defect) structure.

随着我们的研究，我们想要研究限制对各向异性胶体液晶相的影响。由于这也需要使用光学技术，我们将重点从板状针铁矿转移到片状三水铝石颗粒。这些六边形可以用种子生长的方法制备出具有光学可达直径的六边形，并且原则上可以使其成为荧光的。我们以前发现，天然血小板形成了向列相和两种类型的柱状相：一种是具有长程2D有序的六方相，另一种是取向有序但缺乏真正的长程位置有序的六方相。由于这与柱子波动的可能性和缺陷的发生有内在的联系，我们的研究目标之一是研究不同几何形状(缝隙、楔形)中的限制和锚定如何影响六边形和六边形的顺序。我们还打算使用带图案的表面来研究楔形柱的填充。研究这些受限系统的一项重要技术是微射线x射线衍射，但新开发的同步加速器技术，如x射线显微镜，也可能是有趣的。这些测量将得到(偏振和/或共焦)光学显微镜的补充，以解决局部(缺陷)结构。