The excited-state hydride release from 10-methyl-9-phenyl-9,10-dihydroacridine (PhAcrH) was investigated using steady-state and time-resolved UV/vis absorption spectroscopy. Upon excitation, PhAcrH is oxidized to the corresponding iminium ion (PhAcr⁺), while the solvent (acetonitrile/water mixture) is reduced (52% of PhAcr⁺ and 2.5% of hydrogen is formed). The hydride release occurs from the triplet excited state by a stepwise electron/hydrogen-atom transfer mechanism. To facilitate the search for improved organic photohydrides that exhibit a concerted mechanism, a computational methodology is presented that evaluates the thermodynamic parameters for the hydride ion, hydrogen atom, and electron release from organic hydrides.

中文翻译：

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走向有机光氢化物：10-甲基-9-苯基-9,10-二氢ac啶的激发态行为

使用稳态和时间分辨的紫外/可见吸收光谱研究了从10-甲基-9-苯基-9,10-二氢ac啶（PhAcrH）释放出的激发态氢化物。激发后，PhAcrH被氧化成相应的亚胺离子（PhAcr ⁺），同时溶剂（乙腈/水混合物）被还原（形成52％的PhAcr ⁺和2.5％的氢）。通过逐步的电子/氢原子转移机理，从三重激发态释放出氢化物。为了促进寻找具有协同作用机理的改进的有机光氢化物，提出了一种计算方法，该方法可评估氢化物离子，氢原子和有机氢化物释放的电子的热力学参数。