The solvatochromic studies in a Quinoline derivative molecule namely Quinolin-8-ol (QO) have been carried out at ambient temperature using absorption and fluorescence spectroscopy. The QO molecule shows the bathochromic shift with increase in solvent polarity demonstrating π → π* transition. The solvatochromic data coupled with quantum mechanical calculations has been used to estimate change in dipole moment of the molecule after excitation. It has been found that excited state dipole moment is greater than the corresponding ground state dipole moment. Further, it is observed that excited and ground state dipole moments are parallel. The chemical reactivity and kinetic stability of QO molecule are investigated using Frontier molecular orbital (FMO) analysis. Natural bond orbital (NBO) analysis shows proton transfer within the selected donor-acceptor depicting large energy of stabilization for QO molecule. The calculated Fukui functions infer the local softness and local eletrophilicity index of QO molecule. The theoretically simulated UV-Vis absorption spectrum of QO molecule matches well with the experimental spectrum.

中文翻译：

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检查喹啉衍生物的光谱特征和量子化学计算：对光物理特性的实验和理论见解

在喹啉衍生物分子即喹啉-8-醇（QO）中的溶剂变色研究已经在环境温度下使用吸收和荧光光谱法进行。QO分子随溶剂极性的增加而出现红移，表明π→π *过渡。溶剂变色数据与量子力学计算相结合已被用于估计激发后分子的偶极矩的变化。已经发现，激发态偶极矩大于相应的基态偶极矩。此外，观察到激发态和基态偶极矩是平行的。使用Frontier分子轨道（FMO）分析研究了QO分子的化学反应性和动力学稳定性。天然键轨道（NBO）分析显示质子在选定的供体-受体内转移，表明QO分子具有稳定的大能量。计算得出的Fukui函数可以推断QO分子的局部柔软度和局部亲电指数。理论上模拟的QO分子的UV-Vis吸收光谱与实验光谱非常吻合。