将原子和分子放入化学开放的富勒中
Christopher M Stanisky1, R James Cross, Martin Saunders
1Dept. of Chemistry, Yale University, Box 208107, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society
|February 13, 2009
概括
我们研究了像 (Ar) 这样的气体如何进入和退出富勒烯分子. 阿贡对富勒烯产生了强烈的吸引力,这表明存在显著的范德瓦尔斯力.
科学领域:
- 超分子化学 超分子化学
- 物理化学 物理化学
- 纳米技术纳米技术
背景情况:
- 富勒伦是以碳为基础的分子,具有独特的子状结构.
- 将原子或分子封装在富勒伦 (内体富勒伦) 中是研究的一个关键领域.
- 了解富勒烯内的客分子动态对于它们的应用至关重要.
研究的目的:
- 为了研究各种气体分子在化学开放的富勒烯中的封装和释放动力学.
- 为了确定客-富勒烯相互作用的平衡常数和反应速率.
- 阐明影响封装物种结合强度和动态的因素.
主要方法:
- 气体吸附和脱附的测量.
- 确定宾客封装的平衡常数 (Keq).
- 动力学研究来测量速度常数和客人释放的激活能量.
- 在单分子解离反应中分析前指数因子.
主要成果:
- 衡量了与富勒烯1相互作用的 (Ar), (Kr),一氧化碳 (CO) 和 (N2) 的平衡常数 (Keq).
- 对于Ar,观察到一个特别大的Keq,这归因于Ar和富勒烯之间的强范德瓦尔斯吸引力.
- 确定了从富勒烯中单分子释放Ar,CO和N2的速率常数和激活能.
- 对于这些释放反应,发现了异常小的预指数因子,这表明客分子的松结合.
结论:
- 该研究量化了气体封装在富勒伦中的热力学和动力学.
- 范德瓦尔斯力在富勒烯中对像Ar这样的贵重气体的结合中起着重要作用.
- 富勒烯内的客分子的松散结合影响了反应动态,导致了小的预指数因子.
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