压力下替位氢对金属锂能带结构的影响

 利用第一原理的平面波-赝势密度泛函方法，研究了零温下体心立方（bcc）金属锂由于氢的替位掺杂和外界压力的改变所引起的电子结构变化。结果表明：掺杂体系仍然呈金属性，但是由于氢原子俘获了一个金属自由电子，具有了离子属性，使得费米面以下出现了孤立能带和带隙，最低金属价带偏离了自由电子带，形成鞍型带底，其它价带和导带均出现不同程度的简并解除和带型畸变。在压力的作用下，带隙加宽，费米面下的孤立带趋向于一条直线，成为一条能级。

Pressure Effects on the Band Structure of BCC Lithium with Substitutional Hydrogen Defect

The pressure effects on the band structure of bcc lithium with substitutional hydrogen defect are studied by using ab initio pseudopotential-plane wave method at 0 K temperature. Even though the impurity hydrogen atom localizes a free electron in the sea of metallic valence electrons, the doped system still acts as metal, but an isolated band and a band gap appear under Fermi level, the lowest metallic band is distorted at Gamma point, and elsewhere in other conduction and valence bands. When pressures applied on the system, the band gap is widened and the isolated band tends to be stretched horizontally into a line, just like an energy level.