计算化学与紫外-可见吸收光谱法相结合揭示铬黑T指示剂的显色和变色机理  

Revealing the Coloration and Color Change Mechanisms of the Eriochrome Black T Indicator through Computational Chemistry and UV-Visible Absorption Spectroscopy

作　　者：李翼 曹兆祥 刘鹏 吴霞[1] 张冬菊[1] Yi Li;Zhaoxiang Cao;Peng Liu;Xia Wu;Dongju Zhang(School of Chemistry and Chemical Engineering,Shandong University,Jinan 250000,China;School of Chemistry and Chemical Engineering,Qufu Normal University,Qufu 273165,Shandong Province,China)

机构地区：[1]山东大学化学与化工学院,济南250000 [2]曲阜师范大学化学与化工学院,山东曲阜273165

出　　处：《大学化学》2025年第3期132-139,共8页University Chemistry

基　　金：国家自然科学基金(22273051);山东省高等教育本科教学改革研究项目(Z2022024,Z2022169);山东省自然科学基金(ZR2022MB131,ZR2023MB072);山东大学教育教学改革研究项目(2024Z07,2023Y061,2023Y103);山东大学实验室建设与管理研究项目(20232201)。

摘　　要：铬黑T是一种常见的金属离子指示剂,其颜色随溶液pH值不同而变化,且与其金属离子络合物颜色有明显差异,可有效指示反应终点,在分析化学领域有广泛应用。本文用计算化学方法研究了铬黑T及其典型金属离子(Mg^(2+)、Ca^(2+))络合物的分子结构,计算了它们的紫外可见光谱,分析了其分子结构与电子光谱之间的内在关联,并使用紫外-可见吸收光谱法测定了不同pH值的铬黑T溶液及其钙、镁络合物的吸收光谱。理论与实验研究相结合阐释了铬黑T指示剂的显色和变色原理,研究结果有助于加深对铬黑T结构-性能关系的理解。Eriochrome Black T(EBT)is a widely used metal ion indicator,whose color varies with the pH of the solution and differs significantly from the color of its metal ion complexes.This makes it an effective tool for indicating reaction endpoints,with broad applications in analytical chemistry.In this study,computational chemistry methods were used to investigate the molecular structure of EBT and its complexes with typical metal ions(Ca^(2+)and Mg^(2+)),calculate their UV-visible electronic spectra,and analyze the intrinsic relationship between molecular structure and electronic spectra.Additionally,UV-visible absorption spectroscopy was employed to measure the absorption spectra of EBT solutions and its calcium and magnesium complexes under varying pH conditions.By integrating theoretical and experimental approaches,this study elucidates the mechanisms behind the coloration and color change of EBT,providing insights into the structure-property relationship of this indicator.

关 键 词：铬黑T(EBT) 紫外-可见吸收光谱 计算化学 结构-性能关系 

分 类 号：G64[文化科学—高等教育学] O6[文化科学—教育学]