【摘要】 用第一性原理的密度泛函理论计算了PbSe(001)表面的几何结构和电子特性。计算结果表明:PbSe(001)表面几层原子出现明显的振荡弛豫现象,但没发生重构,第一、二原子间距减小,第二、三层原子间距增大,同时也发现表面层原子出现褶皱。该表面的直接带隙出现在X点,在导带底和价带顶附近出现4个表面共振态,另外两个表面态分别出现在-4.0eV附近和-11.5eV附近。更多还原

【Abstract】 The geometry and electronic properties of PbSe(001) surface was investigated by using the density functioned theory method of firstprinciples.The calculated results show that the(001) surface of the semiconductor do not reconstruct but exhibit oscillatory geometric relaxation to some extent.The to-second layer distance contracts by 5.62% and the second-to-third layer distance expands by near 3.88%,in addition,the surface shows a obvious regularity rumpling.The calculations also show the direct surface band gap of the PbSe(001) surface broadens at the X point.Some p characters and s characters surface resonance states appear mainly near the top of the valence band and the bottom of the conduction band.更多还原