• 文献标题:   Electronic structure of graphene nanoribbons doped with nitrogen atoms: a theoretical insight
  • 文献类型:   Article
  • 作  者:   TORRES AE, FOMINE S
  • 作者关键词:  
  • 出版物名称:   PHYSICAL CHEMISTRY CHEMICAL PHYSICS
  • ISSN:   1463-9076 EI 1463-9084
  • 通讯作者地址:   Univ Nacl Autonoma Mexico
  • 被引频次:   12
  • DOI:   10.1039/c5cp00227c
  • 出版年:   2015

▎ 摘  要

The electronic structure of graphene nanoribbons doped with a graphitic type of nitrogen atoms has been studied using B3LYP, B2PLYP and CAS methods. In all but one case the restricted B3LYP solutions were unstable and the CAS calculations provided evidence for the multiconfigurational nature of the ground state with contributions from two dominant configurations. The relative stability of the doped nanoribbons depends mostly on the mutual position of the dopant atoms and notably less on the position of nitrogen atoms within the nanoribbon. N-graphitic doping affects cationic states much more than anionic ones due the participation of the nitrogen atoms in the stabilization of the positive charge, resulting in a drop in ionization energies (IPs) for N-graphitic doped systems. Nitrogen atoms do not participate in the negative charge stabilization of anionic species and, therefore, the doping does not affect the electron affinities (EAs). The unrestricted B3LYP method is the method of choice for the calculation of IPs and EAs. Restricted B3LYP and B2PLYP produces unreliable results for both IPs and EAs while CAS strongly underestimates the electron affinities. This is also true for the reorganization energies where restricted B3LYP produces qualitatively incorrect results. Doping changes the reorganization energy of the nanoribbons; the hole reorganization energy is generally higher than the corresponding electron reorganization energy due to the participation of nitrogen atoms in the stabilization of the positive charge.