物理化学学报 >> 2011, Vol. 27 >> Issue (11): 2535-2540.doi: 10.3866/PKU.WHXB20111006

热力学,动力学和结构化学 上一篇    下一篇

盐/甲醇体系荧光光谱的分析和指认

吴晓静1, 代云1, 张楠1, 李静2   

  1. 1. 合肥工业大学化学工程学院, 合肥 230009;
    2. 安徽省地质实验研究所, 合肥 230001
  • 收稿日期:2011-06-17 修回日期:2011-07-18 发布日期:2011-10-27
  • 通讯作者: 吴晓静 E-mail:wuxiaojing@ustc.edu

Analysis and Assignment of the Fluorescence Spectra of a Salt/Methanol System

WU Xiao-Jing1, DAI Yun1, ZHANG Nan1, LI Jing2   

  1. 1. School of Chemical Engineering, Hefei University of Technology, Hefei 230009, P. R. China;
    2. Institute for Geoanalysis of Anhui Province, Hefei 230001, P. R. China
  • Received:2011-06-17 Revised:2011-07-18 Published:2011-10-27
  • Contact: WU Xiao-Jing E-mail:wuxiaojing@ustc.edu

摘要: 研究了CaCl2、LiCl 和Ca(NO3)2在甲醇溶液中的荧光光谱, 并对溶液中可能的团簇构型采用密度泛函理论和含时(TD)密度泛函理论中的B3LYP方法进行结构优化和激发能计算. 实验结果表明CaCl2和LiCl 与甲醇形成了具有荧光性质的簇合物, 且随着CaCl2和LiCl 浓度的增加溶液的荧光强度整体呈增强趋势, 而Ca(NO3)2与甲醇相互作用使甲醇发生荧光猝灭. 理论计算得到盐/甲醇溶液中可能存在多种簇合物, 但能使甲醇溶液荧光增强的团簇构型主要为[CaCl(CH3OH)n]+和LiCl(CH3OH)n, 而NO3-与甲醇通过氢键作用形成簇合物的振荡强度几乎为零, 解释了NO3-使甲醇发生荧光猝灭的现象.

关键词: 密度泛函理论, 盐/甲醇团簇, 荧光猝灭, 激发波长

Abstract: Fluorescence spectra of CaCl2, LiCl, and Ca(NO3)2 in methanol were investigated and the structures and excitation energy of possible clusters were optimized by density functional theory (DFT) and time-dependent (TD) DFT theory with B3LYP method. Experimental results indicate that CaCl2 and LiCl are connected to methanol as clusters with good fluorescence properties. A strong increase in fluorescence intensity of CaCl2 and LiCl solutions was observed upon increasing their concentrations. The interaction between Ca(NO3)2 and methanol causes the fluorescence quenching of methanol. The results of the theoretical calculation show that [CaCl(CH3OH)n]+ and LiCl(CH3OH)n clusters strengthen the fluorescence intensity of the salt methanol solution and the oscillator strength of NO3- and the methanol clusters is almost zero. This illustrates the fluorescence quenching phenomenon of the NO3- anion and methanol.

Key words: Density functional theory, Salt/methanol cluster, Fluorescence quenching, Excitation wavelength

MSC2000: 

  • O645