一个溶液中的微粒的原子结构是由宽Q范围中子衍射决定的
Rowan Hargreaves1, Daniel T Bowron, Karen Edler
1STFC-ISIS Neutron Scattering Facility, Didcot, United Kingdom. rowan.hargreaves@stfc.ac.uk
Journal of the American Chemical Society
|August 10, 2011
概括
中子衍射揭示了表面活性剂小粒的原子结构. 这项研究详细介绍了小细胞的形成,揭示了疏水性核心,无序的冠状和溶液中的对子相互作用.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 体科学 体科学 体科学
背景情况:
- 在溶液中由于头部和尾部组的亲和关系,表面活性细胞会自组.
- 现有的模型使用包装参数和静电学来解释微粒大小和形状.
研究的目的:
- 为了确定表面活性剂小粒及其溶液中的周围环境的完整的原子结构.
- 为了提供前所未有的细节,关于菌体的物理化学特性.
主要方法:
- 广泛的Q范围中子衍射测量.
- 在H/D的同位素替代中,使用了二甲基三甲基化 (C(10) 溶液.
主要成果:
- ~45个表面活性物分子形成球形的小粒 (旋转半径14.2 Å).
- 较大的菌体表现出更多的圆形状.
- 一个干燥的疏水核被一个由头组, counterions,水和基团组成的冠状环绕着.
- 斯特恩层含有0.7个化物对子/表面活性剂分子,保留了水化.
结论:
- 中子衍射提供了微粒结构的原子分辨率.
- 这些发现与之前关于菌体属性的实验研究一致.
- 详细了解了微粒-溶剂界面和对子行为.
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