DFT and TB study of the geometry of hydrogen adsorbed on graphynes

摘要: Using density-functional calculations (DFT) and a tight-binding model, we investigate the origin of distinct favorable geometries which depend on type graphyne used. The change in H geometry is described terms tuning hopping between sp2-bonded C atoms sp-bonded hybridized with atoms. We find that different preferred for each associated electronic effects due to symmetries rather than steric effect minimizing repulsive interaction band gaps are significantly tuned as varies, except α-graphyne, agreement result our previous DFT study (Koo J et al 2013 J. Phys. Chem. 117 11960). Our model can be used describe properties hydrogenated graphynes.