LiBH_4高压相电子结构第一性原理

Ab initio calculation of higher-pressure phase electronic structure of LiBH_4

目的研究LiBH4高压相的电子结构。方法采用基于密度泛函理论(DFT)的VASP计算程序包在广义梯度近似(GGA)下选用(PBE)赝势处理电子与电子之间的泛函、第一布里渊区k点采样用Monkhorst-Pack方案对能带、态密度(DOS)及分波态密度(PDOS)进行了计算。结果 LiBH4高压相是一种共价键与离子键混合的绝缘体。结论这类绝缘体是由于高压晶相内存在着非金属元素原子和H原子间极强的共价键所导致。在高压相中非金属元素原子与不同H原子形成的共价键不同。

Aim To study higher-pressure phase electronic structure of LiBH4.Methods Calculating the band structure and density of states（DOS） of LiBH4 based on the density function theory with GGA exchange-correlation function implemented in VASP package.Results LiBH4 is insulator with mixed ionic and covalent bond.Conclusion The strong covalent bond between atom H and non-metal atoms leads to the insulation existing in the high-pressure phase.The non-metal atom has a different covalent bond with different atom H in high-pressure phase.