The quantum-chemical and spectroscopic methods make it possible to record the features of photoactivated processes occurring within and between molecules, as well as the structural rearrangements of molecules. To solve the fundamental problem of establishing a relationship between the photophysical and spectral-luminescent properties of organic molecules and their structure, a comparative analysis of the nature of electronically excited states and photoprocesses in coumarin and its related compounds (furocoumarin and 8-methoxypsoralen) has been carried out. To understand the mechanism of forming the absorption and fluorescence spectra of compounds, the schemes of electronically excited states of the molecules under study and the charge localization on the molecular orbitals have been calculated and analyzed. The investigated compounds are effective sensitizers, and the presence of the OCH3 group in the molecular structure has the strongest effect on the spectral-luminescent characteristics. This paper presents the results of studying the induced absorption spectra of 8-methoxypsoralen by the pumb-probe method with a delay of 30 ns in the range of 350–700 nm. The experimentally recorded induced absorption of 8-methoxypsoralen belongs to long-living photoproducts of a radical nature.

中文翻译：

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香豆素敏化剂中的光物理过程

量子化学和光谱方法可以记录分子内部和分子之间发生的光活化过程的特征，以及分子的结构重排。为了解决建立有机分子的光物理和光谱发光特性与其结构之间关系的基本问题，对香豆素及其相关化合物（呋喃香豆素和 8-甲氧基补骨脂素）中电子激发态和光过程的性质进行了比较分析。进行了。为了理解形成化合物的吸收和荧光光谱的机制，我们计算和分析了所研究分子的电子激发态和分子轨道上的电荷定位。研究的化合物是有效的敏化剂，分子结构中 OCH3 基团的存在对光谱发光特性的影响最强。本文介绍了通过 pumb-probe 方法在 350–700 nm 范围内延迟 30 ns 来研究 8-甲氧基补骨脂素的诱导吸收光谱的结果。实验记录的 8-甲氧基补骨脂素的诱导吸收属于自由基性质的长寿命光产物。