在电子转移过程中对电子进行光学控制
I B Martini1, E R Barthel, B J Schwartz
1Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095-1569, USA.
Science (New York, N.Y.)
|July 21, 2001
概括
五秒激光脉冲控制电子转移反应. 在直接接触对中激发电子会阻止反向转移,而在溶剂分离的对中激发电子对离子的产生有不同的影响.
科学领域:
- 化学动力学 化学动力学
- 物理化学 物理化学
- 摄影化学的使用.
背景情况:
- 溶液中的电子转移反应是许多化学过程的基础.
- 控制这些反应对于开发新的化学转化和技术至关重要.
- 电荷转移到溶剂 (CTTS) 反应为研究电子动态提供了一个模型系统.
研究的目的:
- 研究使用连续的五秒激光脉冲来控制电子转移动态.
- 阐明不同接触对配置在四二中化物的CTTS反应中的作用.
- 了解目标电子激发如何影响回电子转移速率.
主要方法:
- 使用一个序列的三个femtosecond激光脉冲启动,操纵和监控CTTS反应.
- 在四基中生成化物 (Na-) 并通过初始脉冲启动CTTS反应.
- 使用第二次脉冲来激发直接或溶剂分离的接触对中的电子 (Na0:溶解电子).
- 监测Na-生产通过使用第三脉冲的回电子转移.
主要成果:
- 最初的脉冲成功启动了CTTS反应,形成Na0:solvated电子接触对.
- 直接接触对中的电子的激发有效地抑制了回电子转移,防止了Na-改造.
- 溶剂分离的电子对中的电子激发表现出双重效应,既增强又阻碍了反向电子传输.
- 接触对的特定配置显著影响电子激发过程的结果.
结论:
- 连续的五秒激光脉冲提供了一种精确的方法来控制溶液中的电子转移动态.
- 接触对中的电子和阴离子的空间排列决定了对外部光学刺激的反应.
- 这项研究展示了一种通过操纵中间电子状态来选择性控制反应结果的途径.
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