It is known that trans,cis,cis-[RuCl₂(DMSO)₂(H₂O)₂] (1a) complexes, which are formed upon dissolution of trans-[RuCl₂(DMSO)₄] in water, demonstrate light-induced cytotoxicity. The mechanistic study of 1a photochemistry has been performed using ultrafast pump–probe spectroscopy, laser flash photolysis and stationary photolysis. The first stage of 1a photochemistry is the photoexchange of a DMSO ligand to a water molecule; its quantum yield is wavelength-dependent (estimating by values 0.3 and 0.04 upon irradiation at 308 and 430 nm, respectively). The mechanism of photoexchange is complicated involving at least four Ru(II) intermediates. Two tentative mechanisms of the process are proposed.

中文翻译：

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水溶液中反式，顺式，顺式[RuCl2（DMSO）2（H2O）2]络合物光化学的机理研究。

众所周知，反式，顺式，顺式-[RuCl ₂（DMSO）₂（H ₂ O）₂ ]（1a）配合物是在水中溶解反式-[RuCl ₂（DMSO）₄ ]形成的。诱导的细胞毒性。已使用超快泵浦-探针光谱，激光闪光光解和固定光解对1a光化学进行了机理研究。1a的第一阶段光化学是DMSO配体与水分子的光交换；它的量子产率与波长有关（在308和430 nm照射时分别估计值为0.3和0.04）。光交换的机制很复杂，涉及至少四个Ru（II）中间体。提出了该过程的两种尝试性机制。