双分子光诱导在溶液中的烯的对称性破坏电荷分离
1Department of Physical Chemistry, University of Geneva, Quai Ernest Ansermet 30, 1205, Geneva, Switzerland.
概括
光诱导的破坏对称性的电荷分离 (SB-CS) 从相同的分子中产生电荷载体. 这项研究表明,SB-CS在极性溶剂和离子液体中发生,增强电荷载体生成.
科学领域:
- 摄影化学的使用.
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
背景情况:
- 光诱导的对称性破坏电荷分离 (SB-CS) 涉及到相同的光激发分子之间的电子转移.
- 在产生自由离子的有机分子中研究SB-CS是具有挑战性的,因为它在高度下具有可溶性和聚合性.
- 以前的研究往往侧重于共价连接的系统.
研究的目的:
- 在高度下研究烯 (Pe) 的兴奋状态动态.
- 探索溶剂极性对SB-CS和排外体形成的影响.
- 确定有利于高效SB-CS用于电荷载体生成的条件.
主要方法:
- 短暂的吸收光谱在次纳秒到微秒的时间尺度上.
- 在不同极性的溶剂中高度使用的烯 (Pe).
- 检查了除菌体形成和双分子SB-CS.
主要成果:
- 激发烯的自我灭导致所有溶剂中的脱体形成.
- 双分子SB-CS生成自由离子的过程与极地介质中的脱体形成同时发生.
- 随着溶剂极性而增加SB-CS效率,并且在离子液体中最高.
结论:
- 高度的烯可促进双分子SB-CS和排外体的形成.
- 极地溶剂和离子液体通过SB-CS促进自由离子生成.
- 离子液体通过电荷屏蔽和高粘度提高了SB-CS的效率.
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