...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Giant-block twist grain boundary smectic phases
【24h】

Giant-block twist grain boundary smectic phases

机译：巨块扭曲晶界近晶相

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Study of a diverse set of chiral smectic materials, each of which has twist grain boundary (TGB) phases over a broad temperature range and exhibits grid patterns in the Geandjean textures of the TGB helix, shows that these features arise from a common structure: "giant" smectic blocks of planar layers of thickness I-b > 200 nm terminated by GBs that are sharp, mediating large angular jumps in layer orientation between blocks (60 degrees < Delta < 90 degrees), and lubricating the thermal contraction of the smectic layers within the blocks. This phenomenology is well described by basic theoretical models applicable in the limit that the ratio of molecular tilt penetration length-to-layer coherence length is large, and featuring GBs in which smectic ordering is weak, approaching thin, melted (nematic-like) walls. In this limit the energy cost of change of the block size is small, leading to a wide variation of block dimension, depending on preparation conditions. The models also account for the temperature dependence of the TGB helix pitch.
机译：对各种各样的手性近晶材料的研究表明，每种手性近晶材料在较宽的温度范围内具有扭曲晶界（TGB）相，并在TGB螺旋的Geandjean纹理中显示出网格图案，这些特征来自共同的结构：“厚度为Ib> 200 nm的平面层的巨型”近晶块，以GBs终止，这些GB尖锐，介导了块之间层取向的大角度跳跃（60度

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号