本文以第一原理計算研究氫化石墨烯的電子性質，結果顯示氫化石墨烯的幾何結構、能帶、電荷分佈和態密度與氫化的結構和濃度有強烈相關。這裡使用三種最佳化週期性結構，其中只有鋸齒形系統可以因氫原子的吸附而顯著地調製能隙大小，並存在中能隙半導體、窄能隙半導體、和無能隙系統這三種類型。此處能帶亦展現出豐富的性質，包括狄拉克錐的破壞與恢復、新形成的臨界點、弱色散關係能帶、和與碳-氫相關的部分扁平能帶。這些都能和軌道投影態密度的低能顯著峰、狄拉克δ函数近似峰、不連續肩狀結構、和對數發散峰互為印證。同時，態密度和空間電荷分佈清楚地指出碳-碳和碳-氫之間關鍵的鍵結是這些多樣化特性的成因。

The electronic properties of hydrogenated graphenes are investigated with the first-principles calculations. Geometric structures, energy bands, charge distributions, and density of states (DOS) strongly depend on the different configurations and concentrations of hydrogen adatoms. Among three types of optimized periodical configurations, only in the zigzag systems the band gaps can be remarkably modulated by H-concentrations. There exist middle-gap semiconductors, narrow-gap semiconductors, and gapless systems. The band structures exhibit the rich features, including the destruction or recovery of the Dirac-cone structure, newly formed critical points, weakly dispersive bands, and (C,H)-related partially flat bands. The orbital-projected DOS are evidenced by the low-energy prominent peaks, delta-function-like peaks, discontinuous shoulders, and logarithmically divergent peaks. The DOS and spatial charge distributions clearly indicate that the critical bondings in C–C and C–H is responsible for the diversified properties.

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