[5,6]-C60O的可逆二元化
Dmitri Tsyboulski1, Dieter Heymann, Sergei M Bachilo
1Department of Chemistry, and Center for Nanoscale Science and Technology, Rice University, 6100 Main Street, Houston, Texas 77005, USA.
Journal of the American Chemical Society
|June 10, 2004
概括
一个新发现的富勒烯氧化物异构体[5,6]-C(60) O,很容易二聚变为C(120) O(2). 这种二聚体可以有效地进行光解离,以再生单聚体,为[5,6]-C(60) O生产提供稳定的途径.
科学领域:
- 富勒烯化学 富勒烯化学
- 超分子化学 超分子化学
- 摄影化学的使用.
背景情况:
- C(60) O 的 [5,6] 开放异构体是最近发现的烯衍生物.
- 富勒烯二元体具有独特的结构和光物理性质.
研究的目的:
- 为了研究[5,6]-C(60) O.O. 的二元化.
- 为了描述产生的二次体的结构和光物理性质,C(120) O(2).
- 探索C(120) O(2) 的光解离,用于再生[5,6]-C(60) O.
主要方法:
- (13)C 核磁共振光谱学
- 一开始的量子计算.
- 高性能液体色谱 (HPLC) 是一种高性能液体色谱.
- 光物理测量 (吸收,光,三重生命周期)
- 对于光解离的量子产量确定.
主要成果:
- [5,6]-C(60) O自发二聚变,形成一个对称的,非极性C(120) O(2) 异构体,由两个sp(3) 混合的碳-碳单键连接在一起.
- C(120) O(2) 呈现出明显的吸收 (峰值在329nm,S(1) -S(0) 在704nm) 和光谱.
- C(120) O(2) 的三重状态寿命为34 ± 2μs.
- 通过C(120) O(2) 的光解离,可再生单体[5,6]-C(60) O,在70°C时的量子产量高达43%.
结论:
- 在温和的条件下,C(120) O(2) 二次体作为光分解生成[5,6]-C(60) O的稳定前体.
- [5,6]-C(60) O及其二元存在于可由外部因素控制的动态平衡中.
- 这种富勒烯添加物具有专门合成应用的潜力.
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