应用平面波展开和第一原理赝势法研究了锂铝单晶的电子和几何结构,给出LiAl各种可能结构的能量～体积关系图以及相关的能带结构,电子态密度和电荷密度分布等各种性质变化关系.讨论了B32结构与其他结构电子键合性质的不同,指出B32结构之所以成为LiAl最稳定的结构是由于Al＿Al原子形成了类似于Si＿Si的共价键合.计算得到的能量最低的稳定结构与实验以及其它的理论计算结果一致.
LiAl is an important anode material for lithium batteries. Based on the plane_wave method and first_principles pseudopotentials, the electronic and geometric properties of LiAl have been studied. The cohesive energies versus volumes of unit cell, energy band structures, electronic density of states and charge density distributions of LiAl under some important structures are presented. The reason of B32_structure as the ground_state of LiAl crystal has also been elucidated, which is owing to Al_Al atoms in B32_structure form strong diamond_type covalent bonds. The present theoretical ground state structure of LiAl is consistent with the experimental and other theoretical results.
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