富勒内部的两个原子:探测C60(6-) 和C70(6-) 中的内部磁场
Tamar Sternfeld1, Roy E Hoffman, Martin Saunders
1Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Journal of the American Chemical Society
|July 26, 2002
概括
像C60这样的富勒伦可以封装两个原子,形成二化合物. 这项研究使用3He NMR识别了He2@C606-,揭示了对内分体富勒烯化学的洞察力.
科学领域:
- 超分子化学 超分子化学
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
背景情况:
- 原子被封装在富勒烯内的内分体富勒烯具有重要的科学意义.
- 之前的研究已经确定了富勒烯中单个原子的封装,但多个原子的可能性尚未得到探索.
研究的目的:
- 为了研究烯子的潜力,特别是C60,封装超过一个原子.
- 使用先进的光谱技术来描述由此产生的二富勒烯物种.
主要方法:
- 使用3He核磁共振 (NMR) 光谱检测和识别原子在烯结构内.
- 在C606和C706衍生物中比较的NMR信号,以区分单和双物种.
主要成果:
- 一个新的3He NMR共振被分配给二富勒烯化合物He2@C606-,证实C60确实可以容纳两个原子.
- 发现二与单C606的比率为1:200,明显低于C70.0所观察到的比率.
- 对He2@C606-的3He NMR化学转移观察到与He@C606-相比的下场0.093 ppm,而He2@C706-与He@C706-相比显示了0.154 ppm的上场转移.
结论:
- 这项研究提供了确定证据,证明二内分体富勒伦与C60.60的形成.
- 与其C70对应物相比,He2@C606-的丰度较低,这表明子大小和应变影响了双原子封装.
- 核磁共振化学转移数据提供了有关电子环境和不同富勒烯内的原子相互作用的见解.
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