Zhang Chao-Jiang, Dai Wen-Shuai, Xu Hong-Guang, Xu Xi-Ling, Zheng Wei-Jun
Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
J Phys Chem A. 2022 Aug 25;126(33):5621-5631. doi: 10.1021/acs.jpca.2c04754. Epub 2022 Aug 16.
Carbon-doped aluminum cluster anions, AlC ( = 6-15), were generated by laser vaporization and investigated by mass-selected anion photoelectron spectroscopy. The geometric structures of AlC ( = 6-15) anions were determined by the comparison of theoretical calculations with the experimental results. It is found that the most stable structure of AlC is a carbon endohedral triangular prism. The AlC anion is a magic cluster with high stability. The structures of AlC can be viewed as the additional aluminum atoms attached around the triangular prism AlC. Two isomers of AlC have been detected in the experiments. The most stable one has a planar tetracoordinate carbon structure. The second one derives from AlC with the carbon atom located in a pentagonal bipyramid. The AlC anion has a bilayer structure composed of one planar tetracoordinate carbon and one aluminum-centered hexagon, in which the major interactions between two layers are multicenter bonds. The structures of AlC can be viewed as evolving from AlC by adding aluminum atoms to interact with the carbon atom. In AlC, the carbon atom stays at the surface with a tetracoordinate structure, and an icosahedral Al unit can be identified as a part of the geometric structure of AlC.
通过激光蒸发产生了碳掺杂铝团簇阴离子AlC（n = 6 - 15），并采用质量选择阴离子光电子能谱对其进行了研究。通过将理论计算结果与实验结果进行比较，确定了AlC（n = 6 - 15）阴离子的几何结构。发现AlC最稳定的结构是碳内包三棱柱。AlC阴离子是具有高稳定性的幻数团簇。AlC的结构可看作是在三棱柱AlC周围附着了额外的铝原子。实验中检测到了AlC的两种异构体。最稳定的一种具有平面四配位碳结构。第二种异构体源自AlC，其中碳原子位于五角双锥中。AlC阴离子具有由一个平面四配位碳和一个以铝为中心的六边形组成的双层结构，两层之间的主要相互作用是多中心键。AlC的结构可看作是通过添加铝原子与碳原子相互作用而从AlC演化而来。在AlC中，碳原子以四配位结构位于表面，并且可以将一个二十面体铝单元识别为AlC几何结构的一部分。
