带状球体石的圆形双断裂
Xiaoyan Cui1, Alexander G Shtukenberg, John Freudenthal
1Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003.
Journal of the American Chemical Society
|March 15, 2014
概括
带状球体中圆形双折是由于扭曲的,伸展的片引起的,而不是自然的光学活动. 这种中等尺度立体化学解释了各种晶体材料的光学特性.
科学领域:
- 固态物理 固态物理
- 材料科学是一种材料科学.
- 晶体学 晶体学是指结晶学.
背景情况:
- 多晶材料通常在线性双折中表现出辐射振荡.
- 化合物的自然光学活性通常解释循环双断.
- 缺乏自然光学活性的中心对称晶体,为观察到的圆形双折射呈现了一个难题.
研究的目的:
- 为了研究带状球状物与螺旋绕纤维的圆形双折的起源.
- 为了确定中等尺度的结构特征,而不是分子性质,是否会导致循环双折.
- 分析21种不同的化合物的光学特性,包括分子晶体,聚合物和矿物质.
主要方法:
- 穆勒矩阵极度测量被用来分析晶体的光学特性.
- 进行了定量模拟,以建模循环双断.
- 分析的重点是结晶体的方向,扭曲和伸展的相互作用.
主要成果:
- 在球状石中观察到的圆形双断裂不仅仅是由于化合物的自然光学活性.
- 圆形双折归因于错误的方向,重叠的异型片.
- 由螺旋扭转过程中被限制所驱动的状伸展产生了这种介质尺度光学活动.
结论:
- 折射元件的中等尺度立体化学,特别是叶片扭曲和伸展,是这些球状物中圆形双折的主要原因.
- 这些发现挑战了在晶体组合中光学活动的传统解释.
- 这种机制为各种材料类型的光学特性提供了统一的解释.
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