在Fe2(CO) 6 ((mu-S2) 的光化学反应中,蝶二基中间体
Ioan Silaghi-Dumitrescu1, Thomas E Bitterwolf, R Bruce King
1Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Cluj-Napoca, Romania.
Journal of the American Chemical Society
|April 20, 2006
概括
四面体Fe2 ((CO) 6 ((mu-S2) 的光解产生了一种蝶单片二基同位素. 密度函数理论计算证实了在更高能量的光解时的结构和CO损失.
科学领域:
- 有机金属化学 有机金属化学
- 摄影化学的使用.
- 计算化学是一种计算化学.
背景情况:
- 四面体群是具有独特结合的有趣结构.
- 了解它们的光化学反应性是探索新型分子转换的关键.
- 铁硫集群在各种催化过程中具有重要意义.
研究的目的:
- 为了研究四面体Fe2(CO) 6 ((mu-S2) 的光化学行为.
- 使用光谱和计算方法对光产品进行表征.
- 阐明光异构体的结构和电子特性.
主要方法:
- 低温矩阵隔离光解Fe2(CO) 6(mu-S2) 在450nm.
- 红外光谱学用于监测碳 (CO) 拉伸频率.
- 密度函数理论 (DFT) 计算使用BP86函数用于结构和振动分析.
主要成果:
- 在450nm的光解产生了一种光异构体,被确定为蝶单片二基Fe2(CO) 6S2.2.
- 实验性的红外频率与DFT计算相匹配,证实了断裂的S-S键和保留的Fe-Fe键.
- 高能光解 (420-280纳米) 导致了CO损失,形成了Fe2(CO) 5S2同位素.
结论:
- 这项研究成功地确定了一种新的蝶单片二基同位素Fe2(CO) 6S2.2.
- 光解提供了一条通往独特的铁硫集群结构的途径.
- DFT计算对于描述瞬态光异构体和反应机制至关重要.
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