Bi2Te3-xSex(x≤3)同晶化合物电子结构的第一性原理研究

本文采用基于密度泛函理论的第一性原理全势能线性缀加平面波方法(FLAPW),分析了Bi₂Te_3-xSe_x体系中各原子自旋轨道耦合(SOI)的p_1/2修正对体系性质的影响,并对Bi₂Te_3-xSe_x(x≤3)同晶化合物的电子特性进行系统的理论研究,首次计算出Bi₂S 关键词： 2Te_3-xSe_x(x≤3)同晶化合物')" href="#">Bi₂Te_3-xSe_x(x≤3)同晶化合物 第一性原理 电子结构 自旋轨道耦合

First-principles study on the electronic structures of diadochic compounds Bi2 Te3-x Sex ( x ≤ 3)

Based on density functional theory with spin-orbit corrections included, the electronic structures of diadochic compounds Bi₂Te_3-xSe_x(x≤3) have been calculated by first-principles full-potential linearized augmented plane-wave method. The calculated results indicate that spin-orbit interaction is crucial in understanding the gap structure near the Fermi energy. Bi₂Te_3-xSe_x(x≤3) are indirect-gap semiconductors, and there is a saddle point at the Γ point. The density of states near Fermi level mainly consists of p orbitals of each atom. For the chemical bonding of the various layers of atoms, the covalence bond component of X(1)—Bi is stronger than that of X(2)—Bi (X=Te, Se). With the increase of the Se mol ratio in the systems, the unit cell volume is reduced, the energy of the system is increased, and the covalence bond component of Te(1)—Bi, Se(2)—Bi, Se(1)—Bi is gradually enhanced.