▎ 摘　　要

Self-consistent charge-density functional tight binding simulations are performed to study the effects of different doping positions for B atoms on electrical structures in armchair graphene nanoribbons passivated with H atoms at ribbon edges. Fourteen different doping modes of the two B atoms in the ribbon matrix are demonstrated. The variations of the structural, thermal stability and electrical structures of the fourteen modes are elucidated. The band gap of the B atoms doped in armchair graphene nanoribbons (B-AGNRs) decreases significantly. In the meanwhile, with doping the B atoms at different positions, the B-AGNRs present metallicity or semi-conductivity. Band structures and density of states are also affected by the arrangements of these doping atoms. The molecular orbitals on HOMO and LUMO energy levels show that the B atoms and their surrounding C atoms forms the 11 bond, and the size and directivity of the 11 bond change corresponding to different doping positions of the B atoms. Accompany with the formation of covalent bonds between the B and C atoms, Mulliken populations on the B atoms change significantly when they are located at the edge and the bulk positions of the B-AGNRs. These findings on electrical level provide us understanding in adjusting the electronic states of the graphene nano ribbons through doping to meet various requirements for electronic devices based on those nanoribbons.