The structures and spectral properties of three ruthenium complexes with 8-hydroxyquinoline (Hhqn) and their derivatives 2-methyl-8-quinolinoline (H2mqn) and 2-chloro-8-quiolinoline (H2cqn) as ligands (QN = hqn, 2mqn, or 2cqn) were calculated with density functional theory (DFT) at the B3LYP level. The UV-Vis and IR spectra of the three [RuCl(QN)NO]⁻ complexes were theoretically assigned via DFT calculations. The calculated spectra reasonably correspond to the experimentally measured spectra. Photoinduced NO release was confirmed through spin trapping of the electron paramagnetic resonance spectroscopy (EPR), and the dynamic process of the NO dissociation upon photoirradiation was monitored using time-resolved infrared (IR) spectroscopy. Moreover, the energy levels and related components of frontier orbitals were further analyzed to understand the electronic effects of the substituent groups at the 2nd position of the ligands on their photochemical reactivity. This study provides the basis for the design of NO donors with potential applications in photodynamic therapy.

中文翻译：

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作为潜在的NO加成药物的三种[RuCl（QN）NO]-配合物（HQN = 8-Hydroxyquinoline及其衍生物）的结构，光谱性质和光动力反应。

具有8-羟基喹啉（Hhqn）及其衍生物2-甲基-8-喹啉（H2mqn）和2-氯-8-喹啉（H2cqn）作为配体的三种钌配合物的结构和光谱性质（QN = hqn，2mqn或2cqn）是根据密度泛函理论（DFT）在B3LYP级别计算的。三种[RuCl（QN）NO] ^-的紫外-可见光谱和红外光谱理论上通过DFT计算分配配合物。计算的光谱合理地对应于实验测量的光谱。通过电子顺磁共振光谱（EPR）的自旋俘获确认了光诱导的NO释放，并使用时间分辨红外（IR）光谱监测了光辐照下NO分解的动态过程。此外，进一步分析了边界轨道的能级和相关成分，以了解配体第二位取代基对其光化学反应性的电子影响。该研究为NO供体的设计提供了基础，并在光动力疗法中具有潜在的应用前景。