TiB2高压下的电子结构研究

 用自洽的LMTO-ASA方法计算了TiB₂压缩状态下的电子结构。计算中考虑了除自旋-轨道耦合外的所有相对论效应。结果表明，随着压缩程度的增加，Ti-B之间的轨道杂化程度也增加，而在电子能带结构中出现了一个新的赝能隙（Pseudogap）或低谷。该赝能隙与高压下晶体结合更加紧密是联系在一起的。从Ti到B的电荷转移随压缩程度的增加而减小，但在所考虑的压缩范围内，这一效应不显著。

ELECTRONIC STRUCTURE OF TiB_2 UNDER HIGH PRESSURES

The electronic structures of TiB2 in compression have been calculated by using the self-consistent LMTO-ASA method. All the relativistic effects except spin-orbit coupling are considered. The results indicate that as the degree of compression in creases, Ti-B hybridization is enhanced and another pseudogap or deep valley in the electronic structure appears. This pseudogap is connected with the increased cohesion of crystal under high pressure. Charge transfer from Ti to B decreases with the increase of compression, though this effect is insignificant within the compression range considered.