Quantum yields for disappearance of (COD)PtMe₂ (1a) and (COD)PtMeCl (1b) were determined at 334 nm in C₆D₆ solvent. Chain reactions initiated by formation of a methyl radical were proposed to be the cause of quantum yields higher than unity (Φ = 5.52 ± 0.40 for 1a) when the reaction mixtures included C₄F₉I. The chain reactions were suppressed in the presence of the radical trap 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), which resulted in measured disappearance quantum yields of Φ = 0.037 ± 0.003 for (COD)PtMe₂ and Φ = 0.44 ± 0.02 for (COD)PtMeCl at 334 nm. Weak luminescence was observed for 1a and 1b, and it was determined that emissive decay is not competitive with Pt–CH₃ bond homolysis. DFT studies enabled assignment of both SBLCT and MLCT transitions in the UV/vis spectra of 1a, while 1b only exhibits MLCT transitions. These effects can be attributed to the symmetry of the molecule and its electronic structure.

中文翻译：

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1,5-环辛二烯铂配合物的光化学用于光辅助化学气相沉积

在C ₆ D ₆溶剂中于334 nm下测定（COD）PtMe ₂（1a）和（COD）PtMeCl（1b）消失的量子产率。当反应混合物包含C ₄ F ₉ I时，由甲基的形成引发的链反应被认为是导致量子产率高于一的原因（Φ= 5.52±0.40对于1a）。自由基陷阱2,2,6,6-四甲基-1-哌啶基氧基（TEMPO），对于（COD）PtMe ₂测得的消失量子产率为Φ= 0.037±0.003，对于（COD）PtMeCl则为Φ= 0.44±0.02在334 nm处 观察到弱发光从图1a和1b可以看出，发射衰减与Pt-CH ₃键均质分解没有竞争性。DFT研究可以在1a的UV / vis光谱中分配SBLCT和MLCT跃迁，而1b仅显示MLCT跃迁。这些影响可以归因于分子的对称性及其电子结构。