| In this dissertation, fluorescence and Raman analysis methods were employed to study hydrogen bonding and cluster structures involved in ethanol-water mixture.Firstly, fluorescence spectra of ethanol-water solutions were obtained. The mechanism of fluorescence emission was elucidated, and the model of ethanol-water cluster was proposed. Then, derivative fluorimetry method was employed to analyze the original fluorescence spectra. The result shows that there are 8 types of luminescent cluster molecules, formed by ethanol and water molecules in different ways, existing in the solution. The peak wavelengths of each cluster's fluorescence spectra were measured. content change of each kind of cluster against solution concentration were obtained, and the hydrogen bonding in the solution with cocentraion of 40% was proposed. Besides, fluorescence spectrum of each cluster was obtained by Gaussian decomposition, and the energy gap, relative size, composition of each kind of cluster were studied based on this.The impact of temperature on the cluster association was also determined. The fluorescence spectra of 3 solutions with volume concentration of 10%,50% and 97% were detected in the temperature range of 5～55℃. The result shows the emission shifts to red region with the increasing temperature. It's concluded increasing temperature alters the structure of the luminescent clusters, besides, there is a threshold located in the range of 15～25℃, clusters of H2O(EtOH)n are the dominant conformation when temperature is below the threshold, but when the temperature excess this threshold, structure rearrangement happens in the mixture and larger clusters with the format of (H2O)m(EtOH)n are formed. We also attribute the fluorescence emission around 355nm and 377nm to two kinds of clathrate cluster.In order to study the concentration dependence of the molecular interactions in ethanol-water hydrogen bonded system, Raman spectra of ethanol-water mixtures with different water contents were obtained at room temperature. It was found that the positions of the C-H stretching vibration bands of ethanol molecule showed blue shifts when more water was added into the mixture, however, the C-O stretching vibration band gave an opposite behavior. Based on this law and the hydrogen bonding theories, we analyzed the molecular interactions and the corresponding cluster styles in different concentration stages. A method for determining the content of ethanol in the ethanol-water solution was proposed based on the frequency shift of CH group. The experiment shows both the C-H symmetric stretching vibration band and the CH3 asymmetric stretching vibration band has linear relation with concentration, and Dualistic Linear Regression was employed to propose the measurement model. Furemore, we compared this model with the present method based on intensity parameters, and the result shows the former method has a better accuracy.The hydrogen bonding and cluster structure in the mixture of low ethanol concentration was analyzed through the OH stretching vibration spectra of samples with 0～10% volume concentration. It is shown the water network is strengthened when a small amount of ethanol molecules are added into pure water. Water molecules aggregate around the ethyl groups of ethanol molecules forming a hydration shell. With the addition of more ethanol molecules, they become aggregate together, and the water molecules around enclose the aggregation forming capsule structures. The aggregation of ethanol molecules leads to the weakening of hydrophobic hydration, as a result, the water molecules become escape from the hydration shell forming small water self-association culusters.The research contributes to the study of ethanol-water cluster structures and their physical and chemical characteristics.
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