【摘要】 采用基于密度泛函理论（DFT）的第一性原理计算方法,计算了Mn₄Si₇及Mo掺杂Mn₄Si₇的电子结构和光学性质。计算结果表明Mn₄Si₇的禁带宽度E_g=0.804 e V,Mo掺杂Mn₄Si₇的禁带宽度E_g=0.636 e V。掺杂使得Mn₄Si₇费米面附近的电子结构发生改变,导带底由Γ点转移为Y点向低能方向下偏移,价带顶向高能方向上偏移,带隙变窄。计算还表明Mo掺杂Mn₄Si₇使介电函数、折射率、吸收系数及光电导率等光学性质增加。更多还原

【Abstract】 The electronic structure and optical properties of Mn₄Si₇ and Mn₄Si₇ doped by Mo were calculated by the density functional theory（DFT）based first-principles method.The calculation results show that the bandgap width of Mn₄Si₇E_g=0.804 e V,and the bandgap width of Mo doped Mn₄Si₇E_g=0.636 e V.Doping changes the electronic structure near the Fermi surface of Mn₄Si₇.The bottom of conduction band byΓtransfer to Y points to low-energy,under the direction of migration to the top of valence band offset to high-energy direction,narrow band gap.The calculation also shows that Mo doping Mn₄Si₇ increases the dielectric function,refractive index,absorption coefficient,photoconductivity and other optical properties.更多还原