Xu Shuhong, Liu Fan, Xu Jingkun, Cui Yiping, Wang Chunlei
Advanced Photonics Center, School of Electronic Science and Engineering, Southeast University, Nanjing, 210096, Jiangsu, China.
J Mol Model. 2020 Apr 30;26(5):111. doi: 10.1007/s00894-020-4344-5.
In an experiment, cyclo[18]carbon (C), prepared with low-temperature STM-AFM (scanning tunneling microscopy-atomic force microscopy) from CO, CO, and CO molecules, have been confirmed being alternating single and triple bonds structure. Nevertheless, the stability of C is weak at room temperature in gas. Thus, it is difficult to study the spectrum, orbital, and bonds characters of the C molecule in the experiment. In this paper, we have obtained absorption spectrum, orbital, and bonding characters of the C molecule in theory. Besides, bonds and spectra of CO, CO, CO, BN, C, C, C, and C molecules have been investigated to further confirm the structure and the characters of the C molecule. The results show that carbon-carbon bonds of CO, CO, and CO molecules in ring are alternating single and triple bonds except those connected with CO group. BN molecule as the isoelectronic structure of C has a larger bandgap and shorter wavelength of absorption spectra than those of the C molecule. Moreover, all bonds between boron and nitrogen in BN molecule are single one. Study bonding characters for C, C, C, and C molecules have confirmed that carbon-carbon bonds of cyclo[n]carbon changed gradually from double bonds to alternating single and triple bonds with increasing n value. The data from theory would give help for future research on C and BN molecules in experiment. Graphical abstract Theoretical investigation for bond and spectra characters of cyclo[18]carbon (C), prepared with low-temperature STM-AFM (scanning tunneling microscopy-atomic force microscopy) from CO, CO, and CO molecules, which have been confirmed being alternating single and triple bonds structure.
在一项实验中，通过低温扫描隧道显微镜-原子力显微镜（STM-AFM）由一氧化碳、二氧化碳和一氧化碳分子制备的环[18]碳（C）已被证实具有单键和三键交替的结构。然而，C在室温下的气态稳定性较弱。因此，在实验中难以研究C分子的光谱、轨道和键的特征。在本文中，我们从理论上获得了C分子的吸收光谱、轨道和键合特征。此外，还研究了一氧化碳、二氧化碳、一氧化碳、氮化硼、C₂、C₃、C₄和C₅分子的键和光谱，以进一步确认C分子的结构和特征。结果表明，环内一氧化碳、二氧化碳和一氧化碳分子的碳-碳键，除了与羰基相连的那些键外，是单键和三键交替的。作为C的等电子结构的氮化硼分子，其带隙比C分子大，吸收光谱的波长更短。此外，氮化硼分子中硼和氮之间的所有键都是单键。对C₂、C₃、C₄和C₅分子键合特征的研究证实，随着n值的增加，环[n]碳的碳-碳键逐渐从双键变为单键和三键交替。理论数据将为未来对C和氮化硼分子的实验研究提供帮助。图形摘要 通过低温扫描隧道显微镜-原子力显微镜（STM-AFM）由一氧化碳、二氧化碳和一氧化碳分子制备的环[18]碳（C）的键和光谱特征的理论研究，已证实其具有单键和三键交替的结构。
