Edge saturation effects on the magnetism and band gaps in multilayer graphene ribbons and flakes

Article

关键词: GENERALIZED GRADIENT APPROXIMATION;    GAS CORRELATION-ENERGY;    ELECTRON-GAS;    CARBON NANOTUBES;    NANORIBBONS;    STATE;   

DOI  :  10.1103/PhysRevB.84.075481

来源: SCIE

【 摘 要 】

Using a density functional theory based electronic structure method and semilocal density approximation, we study the interplay of geometric confinement, magnetism, and external electric fields on the electronic structure and the resulting band gaps of multilayer graphene ribbons, the edges of which are saturated with molecular hydrogen (H(2)) or hydroxyl (OH) groups. We discuss the similarities and differences of computed features in comparison with the atomic hydrogen (or H-) saturated ribbons and flakes. For H(2) edge saturation, we find shifted labeling of three armchair ribbon classes and magnetic to nonmagnetic transition in narrow zigzag ribbons, the critical width of which changes with the number of layers. Other computed characteristics, such as the existence of a critical gap and external electric field behavior, layer-dependent electronic structure, stacking-dependent band-gap induction, and the length confinement effects remain qualitatively the same with those of H-saturated ribbons.

【 授权许可】

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