1. School of Science, Jiangnan University, Wuxi 214122, China
2. School of Internet of Things Engineering, Jiangnan University, Wuxi 214122, China
3. Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, Wuxi 214122, China
Abstract：The absorption and the emission spectra of methanol and ethanol, scanned by the Edinburgh FLS920P steady-instantaneous fluorescence spectrometer, are studied on this paper. Aiming at comparison on the molecular structuresof methanol and ethanol under different states, we employ the density functional theory (DFT) and the single-excitation configuration interaction (CIS) to optimizemolecular structures under the ground and excited state. The absorption and emission spectra of methanol and ethanol on the base of 6-31++G (d, p) are estimated based on the time-dependent density functional theory (TD-DFT) with the polarized continuous model (PCM), which are in agreements with the experimental results. Furthermore, we analyze the fluorescence mechanism of methanol and ethanol, and investigate the effect caused by different exchange correlation functions on the calculated spectra. The results indicate that methanol and ethanol have weak absorption in ultraviolet regionand produce Raman band and weak fluorescence peaks through UV excitation. Meanwhile, the absorption spectra of methanol and ethanol are produced by Rydberg excitation, of which the orbit jumps from σ* to π*. Our results show that the OLYP function can reproduce the experimental absorption spectrum well and the MPWK function can predict the emission energy well. There exist differences on calculations of transition energy varying from different pure functions. Our results can provide a reliable tool to study alcohols’ molecular properties.
Key words：Fluorescence spectra; Density functional theory; Absorption spectra; Methanol; Ethanol
朱从海，陈国庆，朱 纯，赵金辰，刘怀博，张笑河，宋鑫澍. 基于密度泛函的甲醇和乙醇荧光特性研究[J]. 光谱学与光谱分析, 2018, 38(04): 1133-1138.
ZHU Cong-hai, CHEN Guo-qing, ZHU Chun, ZHAO Jin-chen, LIU Huai-bo, ZHANG Xiao-he, SONG Xin-shu. Studies of the Fluorescence Properties of Methanol and Ethanol Based on the Density Functional Theory. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2018, 38(04): 1133-1138.
