中文摘要：

<正>The TiO2（101） surface was studied using the plane-wave ultrasoft pseudopotential method based on the density functional theory,with emphasis on the structure,surface energy,band structure,density of states, and charge population.The anatase TiO2（101） crystal surface structure,whose outermost and second layers were terminated by twofold coordinated oxygen atoms and fivefold coordinated titanium atoms,was found to be much more stable.The surface energy of the 18-layer atoms model was 0.580 J/m2.The surface electronic structure was similar to that of the bulk and no surface state.Compared with the bulk structure,the band gap increased 0.36 eV, the Ti5c-02c bond lengths reduced 0.171（?） after relaxation,and the charges of the surface were transferred to the body.Analysis of the optical properties of the TiO2（101） surface showed that it did not absorb in the low-energy region.An absorption edge in the ultraviolet region corresponding to the energy of 3.06 eV was found.

英文摘要：

The TiO_2（101） surface was studied using the plane-wave ultrasoft pseudopotential method based on the density functional theory,with emphasis on the structure,surface energy,band structure,density of states, and charge population.The anatase TiO_2（101） crystal surface structure,whose outermost and second layers were terminated by twofold coordinated oxygen atoms and fivefold coordinated titanium atoms,was found to be much more stable.The surface energy of the 18-layer atoms model was 0.580 J/m2.The surface electronic structure was similar to that of the bulk and no surface state.Compared with the bulk structure,the band gap increased 0.36 eV, the Ti5c-02c bond lengths reduced 0.171（？） after relaxation,and the charges of the surface were transferred to the body.Analysis of the optical properties of the TiO_2（101） surface showed that it did not absorb in the low-energy region.An absorption edge in the ultraviolet region corresponding to the energy of 3.06 eV was found.