共享轨道:在bucky铁和ruthenocenes中具有不同的结果的超快激发状态停活
Dirk M Guldi1, G M Aminur Rahman, Renata Marczak
1Universität Erlangen, Institute for Physical and Theoretical Chemistry, 91058 Erlangen, Germany. dirk.guldi@chemie.uni-erlangen.de
Journal of the American Chemical Society
|July 20, 2006
概括
巴基铁联体表现出显著的电荷转移,形成转移稳定的基离子离子对. 由于更快的失活和不利的氧化潜力,Bucky 鲁烯合物没有显示电荷分离.
科学领域:
- 光化学和光物理学
- 有机金属化学 有机金属化学
- 超分子化学 超分子化学
背景情况:
- 富勒-有机金属合物因其电子性质而有趣.
- 铁和鲁丁衍生物具有不同的电子和氧化还原特性.
研究的目的:
- 为了研究巴基铁和巴基鲁丁联体中的基层和兴奋状态电子相互作用.
- 为了比较铁和含系统之间的电荷转移动态和光物理性质.
主要方法:
- 稳态和时间分辨率光光谱学.
- 五秒和纳秒的探头实验.
- 脉冲放射溶解是一种脉冲放射溶解.
主要成果:
- 巴基铁联体显示了从铁到富勒烯的基本状态电荷密度的大幅变化.
- 巴基铁联体的兴奋状态经历快速的电荷分离 (0.8 psi),形成基离子对,寿命为27-39 psi.
- 巴基鲁烯合物不表现出电荷分离;相反,由于较重的中心和不利的氧化潜力,发生了更快的兴奋状态失活 (~200 ps).
结论:
- 巴基铁中的亲密接触使得高效的光诱导电子转移成为可能.
- 的特性,包括其较重的性质和氧化还原潜力,抑制了bucky ruthenocene中的电荷分离,导致快速失活.
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