Structure analysis of adsorbed molecules or ions at liquid-liquid interface by total-reflection X-ray absorption spectroscopy

XAFS(X射线吸收精细结构)技术已被应用于溶剂化离子或分子的局域结构分析。本文发展和改进了全反射荧光XAFS(TrXAFS)方法，用于在液-液界面上原位观察溴离子的结构，并利用该装置从BrK边的XAFS跃迁高度估算了DTAB水溶液-正己烷界面的溴离子吸附量。结果表明，溴离子在水-正己烷界面上的吸附行为与在水溶液表面上的吸附行为不同。采用同步辐射水平极化和垂直极化的TR-XAFS方法研究了疏水的ZnTPP在庚烷-水界面上的分子取向。

XAFS (X-ray absorption fine structure) technique has been applied to the local structure analysis of solvated ions or molecules. Total-reflection fluorescence-XAFS (TR-XAFS) method has been developed and improved for the observations of their structures in situ at the liquid-liquid interface.The amount of adsorbed bromide ions at DTAB aqueous solution-hexane interface has been estimated from XAFS jump height at Br K edge using this TR-XAFS apparatus. It was clear that the adsorption behavior of bromide ions at water-hexane interface was different from that at the aqueous solution surface.The molecular orientation of hydrophobic ZnTPP at heptane-water interface was studied byTR-XAFS method taken horizontal and vertical polarizations of synchrotron radiation.