▎ 摘　　要

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were performed with the basis sets 6-31G for DFT and 6-31G(d), 6-31+G(d,p) for TDDFT on pure graphene nanoribbon (GNR) C30H14 and metal-decorated C29H14-X (MGNRs; X=Ni, Fe, Ti, Co+, Al+, and Cu+). The metal/carbon ratio (X:C 3.45%) and the doping site were fixed. Electronic properties, that is, the dipole moment, binding energy, and HOMO-LUMO gaps, were calculated. The absorption and emission properties in the visible range (=400-720 nm) were determined. Optical gaps, absorption and emission wavelengths, oscillator strengths, and dominant transitions were calculated. Pure graphene was found to be the most stable form. However, of the MGNRs, C29H14Co+ and C29H14Al+ were found to be the most and least stable, respectively. All GNRs were found to have semiconducting nature. The optical absorption of pure graphene undergoes a shift on metal doping. Emission from the pure graphene followed Kashas rule, unlike the metal-doped GNRs.