摘要
采用基于密度泛函理论的局域密度近似(LDA),计算了压力对LixTiS2(x=0,0.25,0.5,0.75,1)的晶格结构和电子结构的影响。研究发现,对于同一Li含量的LixTiS2,随着压力的增大,LixTiS2的晶格参数有规律的减小,插层化合物中Li的含量越高,材料越难被压缩;在压强等于1 GPa左右时各体系的总能量达到最小值。各体系的费米能级随着压力的增大而降低;各原子的电子能态密度产生了漂移,压力还导致了S原子和Ti原子p-d杂化减弱。Li原子和S原子的共价相互作用得到了增强。
Using local density approximation (LDA)to density functional theory,we calculate the effect of pressure on crystal structure and the electron properties of LixTiS2 (x=0,0.25,0.5,0.75,1). The results show that the lattice parameters reduce with the increasing pressure;the compressibility decreases with increasing x; for fixed x,the total energy is lowest at 1 GPa. The pressure results to the red-shift of Fermi energy,the excursion of DOS (density of states),and the weakening of hybridization of S and Ti. The covalence between atoms Li and S becomes strength because of the pressure.
出处
《中国民航大学学报》
CAS
2008年第2期53-56,共4页
Journal of Civil Aviation University of China
基金
中国民用航空学院理学基金项目(05yk25s)