Study on the Elements of the Fluorescence Spectra Emitted from Ethanol-Water Mixture
WU Bin1, LIU Ying2, HAN Cai-qin1, 2, LUO Xiao-sen1*, LU Jian1, NI Xiao-wu1
1. School of Science, Nanjing University of Science & Technology, Nanjing 210094, China 2. College of Physics & Electronic Engineering, Xuzhou Normal University, Xuzhou 221116, China
Abstract：The 236 nm UV-light was adopted to excite the 10 ethanol-water mixture samples in which the volume percent of ethanol ranges from 10% to 95%, and the Gaussian decomposition method was used to decompose the fluorescence spectra obtained above to Gaussian curves，where every Gaussian curve can be attributed to the fluorescence emission of a certain kind of luminescent ethanol-water cluster, which is formed by the association between water molecules and ethanol molecules. It was found that every spectrum of the certain binary mixture contains 8 Gaussian elements, and the emission density and peak wavelength of each element were also obtained. The authors studied the mechanism of the fluorescence emission of the mixtures based on the structural characters of fluorescence substances and concluded that the water molecules play an important role in the fluorescence emission: they enlarge the conjugate system as the electron donors; they bridge the ethanol molecules to form 8 kinds of new clusters at the same time, and the conformation of the clusters is rings and chains composed by several rings. Through the peak wavelengths of the Gaussian elements decomposed from the certain concentration spectrum the authors got the information about the relative size of the new clusters, i.e. the clusters are bigger or show chain structures when the peak wavelength of the Gaussian curves is located at the longer positions. The emission transition energies of the 8 kinds of new clusters were also calculated. In addition, it was found that there was a certain relation between the half-width and the association situation. The research contributes to the study of ethanol-water cluster structures and their physical and chemical characteristics.
吴 斌1，刘 莹2，韩彩芹1，2，骆晓森1*，陆 建1，倪晓武1 . 乙醇-水溶液中团簇分子的基元荧光光谱研究[J]. 光谱学与光谱分析, 2010, 30(05): 1285-1289.
WU Bin1, LIU Ying2, HAN Cai-qin1, 2, LUO Xiao-sen1*, LU Jian1, NI Xiao-wu1 . Study on the Elements of the Fluorescence Spectra Emitted from Ethanol-Water Mixture . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2010, 30(05): 1285-1289.
[1] Lamanna R, Cannistraro S. Chemical Physics, 1996, 213: 95. [2] Andoh Y, Yasuoka K. J. Phys. Chem. B, 2006, 110: 23264. [3] Wakisaka A, Matsuura K. Journal of Molecular Liquids, 2006, 129: 25. [4] Zhang C, Yang X. Fluid Phase Equilibria, 2005, 231: 1. [5] Yu Y, Lin K, Zhou X, et al. J. Phys. Chem. C, 2007, 111: 8971. [6] Tomic M, Jamnik A, Fritz-Popovski G, et al. J. Phys. Chem. B, 2007, 111: 1738. [7] LIU Ying, PENG Chang-de, LAN Xiu-feng, et al(刘 莹，彭长德，兰秀风，等). Acta Physica Sinica(物理学报), 2005, 54: 5455. [8] Liu Y, Luo X S, Shen Z H, et al. Optical Review, 2006, 13: 303. [9] LIU Ying, SONG Chun-yuan, HE Wen-liang, et al(刘 莹，宋春元，何文亮，等). Acta Physica Sinica(物理学报), 2007, 56: 2962. [10] Liu Y, Song C Y, Luo X S, et al. Chinese Physica. 2007, 16: 1300. [11] WU Bin, LIU Ying, HAN Cai-qin, et al. Chinese Optics Letters, 2009, 7: 159. [12] Wang S H, Cann N M. The Journal of Chemical Physics, 2007, 126: 214502. [13] XU Jin-gou, WANG Zun-ben(许金钩、王尊本). Fluorescence Analysis: Edition Three(荧光分析法, 第3版). Beijing: Science Press (北京: 科学出版社)，2006. 22. [14] WU Shi-kang(吴世康). Introduction of Macromolecules Photochemistry-Principle and Application(高分子光化学导论—基础和应用). Beijing: Science Press(北京: 科学出版社), 2003. 247. [15] Herzberg G. Molecular Spectra and Molecular Structure Ⅱ. Infrared and Raman Spectra of Polyatomic molecules(分子光谱与分子结构 Ⅱ. 多原子分子的红外光谱与拉曼光谱). Translated by WANG Ding-chang(王鼎昌译) . Beijing: Science Press(北京：科学出版社), 1986. 69.
