隔离和结晶学识别四个异构体的Sm@C90 Sm@C90 的异构体
Hua Yang1, Hongxiao Jin, Hongyu Zhen
1College of Materials Science and Engineering, China Jiliang University, Hangzhou 310018, China.
Journal of the American Chemical Society
|April 2, 2011
概括
研究人员使用先进的分离和X射线衍射技术确定了四种独特的化内分体富勒烯 (Sm@C90) 异构体. 这项研究提供了迄今为止最全面的内分层富勒烯异构体的结构分析.
科学领域:
- 富勒烯的化学结构
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 内分体富勒烯,其中一个非碳原子被封装在富勒烯内,具有重要的科学意义.
- 这些复杂分子的各种异构体的合成和表征带来了巨大的挑战.
- 化末体烯 (Sm@C90) 是一个具有独特结构可能性的特定类别.
研究的目的:
- 为了分离和结构性阐明Sm@C90.的多个异构体.
- 为了建立一个新的基准,对结构上确定的内向型富勒烯异构体的数量.
- 探索不同异构体之间的结构关系.
主要方法:
- 通过电弧蒸发Sm(2) O(3) 合碳棒合成Sm@C90.
- 使用Buckyprep列的染色学分离,使用烯作为化剂来分离单个异构体.
- 单晶X射线衍射分析与Ni (?? 乙) 形成的共晶体,以确定精确的结构.
主要成果:
- 四种不同的Sm@C90异构体,标记为Sm@C90(I) 到Sm@C90(IV),已成功分离和表征.
- 特定的子结构被确定为Sm@C2(40) -C90,Sm@C2(42) -C90,Sm@C2v(46) -C90,和Sm@C2(45) -C90.
- 这代表了最大的内分体富勒烯异构体,其结构已通过X射线衍射单独确定.
结论:
- 该研究成功地特征了四种独特的Sm@C90异构体,大大推进了内分体富勒烯结构确定领域.
- 已识别的异构体呈现出不同的结构,为富勒烯异构体提供了洞察力.
- 异构体之间的配对结构关系可以通过正式的斯通-威尔士转换来描述.
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