Four isomers of C96 fullerene structurally proven as C96Cl22 and C96Cl24.
Four isomers of C96 fullerene structurally proven as C96Cl22 and C96Cl24.
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DOI：
10.1002/anie.201201775
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发表时间：
2012-08
影响因子：
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通讯作者：
Shangfeng Yang;Tao Wei;E. Kemnitz;S. Troyanov
中科院分区：
文献类型：
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作者：
Shangfeng Yang;Tao Wei;E. Kemnitz;S. Troyanov
高级富勒烯（大于 C70）的研究由于其在富勒烯烟灰中的丰度较低以及遵守孤立五边形规则 (IPR) 的稳定富勒烯异构体的数量随着笼尺寸的增加而迅速增加而受到阻碍。 [1]高级富勒烯的结构表征通常通过 13C NMR 光谱来完成，该光谱提供了分子对称性的信息。然而，在许多情况下，通过这种传统方法鉴定高级富勒烯并不明确，因为几种异构体可能表现出相同的分子对称性。 [2]理论计算提供了有关核磁共振谱中相对稳定性和预期线分布的信息，从而有助于笼分配。 [3]高级富勒烯的衍生化，然后通过直接方法分离衍生物和表征似乎是一种相当有效的方法，正如基于全氟烷基化和卤化衍生物的 C78-C90 的一些例子所说明的那样。[4]对 C90 以上的高级富勒烯的实验观察还受到极少量的可用材料和大量可能需要分离的异构体的阻碍。作为从富勒烯烟灰中分离出来的最大的高级富勒烯之一，根据拓扑分析，C96 预计有 187 种可能的 IPR 笼异构体。 [1] C96 富勒烯的首次色谱分离和 13C NMR 表征表明富勒烯烟灰中存在多达十种不同的异构体。 [5]对 C96 异构体进行理论计算以预测其相对稳定性。根据计算
Investigations of higher fullerenes (larger than C70) have been hampered by their low abundance in fullerene soot and by the fact that the number of stable fullerene isomers obeying the isolated pentagon rule (IPR) increases rapidly with the cage size.[1] Structural characterization of higher fullerenes is typically accomplished by means of 13C NMR spectroscopy which provides information on molecular symmetry. However, the identification of higher fullerenes by this conventional method is not unambiguous in many cases since several isomers may exhibit the same molecular symmetry.[2] Theoretical calculations provide information concerning the relative stability and the expected line distribution in the NMR spectra, thus assisting in the cage assignment.[3] The derivatization of higher fullerenes followed by the separation of derivatives and characterization by direct methods appeared to be a rather effective approach, as illustrated by some examples for C78–C90 based on their perfluoroalkylated and halogenated derivatives.[4]Experimental observations on higher fullerenes beyond C90 are additionally hindered by the very small amounts of available materials and the large number of possible isomers to be separated. As one of the largest higher fullerenes isolable from fullerene soot, C96 is predicted to have 187 possible IPR cage isomers according to the topological analysis.[1] The first chromatographic isolation and 13C NMR characterization of C96 fullerenes indicated the presence of as many as ten different isomers in fullerene soot.[5] Theoretical calculations were performed for C96 isomers to predict their relative stabilities. According to the calcu-