XAFS study of Cu^(2+) in aqueous solution of CuBr_2

作     者：DAI Binbin WANG Qian MA Jingyuan LI Jiong ZHANG Shuo HUANG Yuying HUANG Wei WU Guozhong ZOU Yang JIANG Zheng XU Hongjie 

作者机构：Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China 

出 版 物：《Nuclear Science and Techniques》 (核技术（英文）)

年 卷 期：2012年第23卷第3期

页      面：129-133页

核心收录：

学科分类：081704[工学-应用化学] 081705[工学-工业催化] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070304[理学-物理化学(含∶化学物理)] 0827[工学-核科学与技术] 0703[理学-化学] 0702[理学-物理学] 

基　　金：Supported by National Natural Science Foundation of China (Grant No.11005148,10705046,11135008) National Basic Research Program of China (Grant No. 2010CB934501) Special Presidential Foundation of the Chinese Academy of Science (Grant No. 29) Science and Technology Commission of Shanghai Municipality (Grant No. 11JC1414900) 

主　　题：EXAFS 水溶液 X-射线吸收精细结构 X射线吸收精细结构 X射线吸收近边结构 XANES 傅立叶变换 微量元素 

摘      要：Copper ion is the essential microelement to many organisms. In this paper, the local structure of Cu2+ in CuBr2 aqueous solutions with different concentrations are investigated by using X-ray absorption fine structure (XAFS) technique. XANES (X-ray Absorption Near Edge Structure) spectra indicate that charge transfer from Br- to Cu2+ decreases with the solution concentration, which lead to a shift of the absorption edge. The shoulder appearing at the rising edge proves to be characteristic of a tetragonal distortion. The Fourier transform magnitudes of EXAFS (Extended X-ray absorption fine structure) data of Cu species suggest that more Cu-Br bonds may exist in high concentrations. A fivefold coordination configuration like a pyramid is used as the fitting parameters. From the analysis of the coordination numbers, the proportion of Cu-O and Cu-Br is 4:1 in the saturated solution. The Br atom is on the equatorial plane of the model. The fitting results agree well with the experiment data.