• 文献标题:   Pattern Formation Due to Fluorination on Graphene Fragments: Structures, Hopping Behavior, and Magnetic Properties
  • 文献类型:   Article
  • 作  者:   NIJAMUDHEEN A, DATTA A
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF PHYSICAL CHEMISTRY A
  • ISSN:   1089-5639 EI 1520-5215
  • 通讯作者地址:   Indian Assoc Cultivat Sci
  • 被引频次:   10
  • DOI:   10.1021/jp3122165
  • 出版年:   2013

▎ 摘  要

Structures and mechanism of pattern formation for the radical fluorination on selected polyaromatic hydrocarbons (PAR) has been studied using density functional theory (DFT) methods. Our study reveals that the F. radical addition occurs preferentially at the edges of PAHs followed by the hopping of F. to the center due to the fluxional nature of C-F-. bond. F-. migrates preferentially over the C-C bonds having a lower barrier than that over the aromatic, pi-cloud in cases of monofluorinated PAHs. Addition of a second F-. radical can stabilize the system, cooperatively. When two F are added to the adjacent C atoms, it forms the minimum energy patterns. However, the addition of two fluorine radicals at the meta position of the same aromatic ring would lead to the stabilization of the triplet state compared to the singlet ground state. Therefore, depending on the sites of F-. addition, these structures exhibit ferromagnetic/antiferromagnetic ground states. Considering the low barrier heights for the F-. hopping, these systems are predicted to be in a dynamic equilibrium with their less stable ferromagnetic states. Our study also provides an atomistic understanding of the well-known rate determining state for the fluorine pattern formation in graphene and CNT.