• 文献标题:   Aromaticity of graphene nanoflakes in a new way: fragment analysis by combination of the nucleus-independent chemical shifts and the anisotropy of current induced density
  • 文献类型:   Article
  • 作  者:   LI Q, LI CM, XU HL, SU ZM
  • 作者关键词:   graphene nanoflake, gnf, fragment, nics, acid
  • 出版物名称:   JOURNAL OF MOLECULAR MODELING
  • ISSN:   1610-2940 EI 0948-5023
  • 通讯作者地址:   Yanbian Univ
  • 被引频次:   0
  • DOI:   10.1007/s00894-017-3394-9
  • 出版年:   2017

▎ 摘  要

A graphene nanoflake (GNF) is a polycyclic aromatic hydrocarbon (PAH) with a huge two-dimensional pi-conjugated carbon material in which a central benzene ring is surrounded by identical benzene-type rings through infinite alternant method. In this paper, we explore the structure-aromaticity relationship of the GNFs and the GNFs with hollow sites (GNFHs) by combining the nucleus-independent chemical shifts (NICS) with the anisotropy of the current induced density (ACID). Firstly, the benzene is a typical aromatic molecule (NICS = -9.671 ppm), GNFs 1-6 is darned with benzene and the corresponding GNFHs 1'-6'. Secondly, the NICS values of GNFs 1-6 alternately vary: -1.214 (1) > -13.847 (2) < -2.662 (3) > -14.530 (4) < -3.932 (5) > -13.978 (6) ppm, the GNFs (2, 4, 6) with even fragments of annulene have larger aromaticity than that of GNFs (1, 3, 5) with odd fragments of annulene. Significantly, the NICS values of GNFs 1-6 can also be fragment analyzed by the NICS values and ACID of benzene and corresponding GNFHs 1'-6'. The NICS values for GNFs (2, 4, 6) can be roughly estimated by the NICS value of benzene minus the NICS value of the GNFHs (2', 4', 6'), respectively. The NICS values for GNFs (1, 3, 5) can be roughly estimated by the NICS value of the GNFHs (1', 3', 5') minus the NICS value of benzene, respectively. We hope that the present work can provide a simple and reliable method for the rational design of the GNF with aromaticity, which may be used to understand the origin of the graphene nanoflake aromatic properties.