实验证据证明了较高富勒的光异构化
Clemens Burda1, Anna C S Samia, David J Hathcock
1Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA. burda@po.cwru.edu
Journal of the American Chemical Society
|October 17, 2002
概括
较大的富勒伦显示出较慢的激发状态动态,与同位素数和斯通-威尔斯同位素化机制相关联. 这表明了快速光学网关应用的潜力.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 光物理学的光学物理学
背景情况:
- 富勒 (C60,C70,C76,C84,C86,C90) 是具有独特电子性质的碳类.
- 了解激发状态动力学对于它们在光电子学中的应用至关重要.
- 斯通-威尔士异构化机制描述了碳中的结构变化.
研究的目的:
- 为了研究光激发富勒伦的初始放松动态.
- 为了将动态与富勒伦大小和异构化相关联.
- 探索光学门的潜在应用.
主要方法:
- 没有分散的femtosecond探针光谱学.
- 在可见和近红外 (NIR) 频谱范围内监测动态.
- 对异构化途径的计算分析.
主要成果:
- 兴奋状态的形成会随着富勒伦大小的增加而减缓.
- 动力学与同位素的数量和斯通-威尔士机制相关.
- 斯通-威尔士同质化是光诱导的,没有障碍.
- 同位体的能量差异大约为1 meV.
- 反向异构发生在皮秒时间尺度上.
- 观察到广泛的短暂吸收.
结论:
- 富勒伦的大小和异构性显著影响兴奋状态放松.
- 光诱导的斯通-威尔士异构化是一个关键因素.
- 广泛的瞬态吸收表明了快速光学门装置的潜力.
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