H_2O在LiH固体表面的吸附与成键  

Adsorption and bonding of H_2O on LiH solid surface

作　　者：蔡军[1] 王明玺[1] 薛卫东[1] 邹乐西[2] 

机构地区：[1]四川师范大学化学学院与材料科学学院,成都610066 [2]中国工程物理研究院,绵阳629000

出　　处：《原子与分子物理学报》2006年第1期85-89,共5页Journal of Atomic and Molecular Physics

基　　金：四川省自然科学科研项目(2003A083)

摘　　要：用基于密度泛函理论的局域密度近似平面波超软赝势方法,计算了H2O分子在LiH表面的最佳吸附方式,得到了倾斜吸附的构型,其偏转角为37.85°.由吸附前后的态密度(DOS)图可知,成键主要由LiH的s、p轨道和H2O的sp3轨道杂化而成,成键峰重叠性较强,且峰增宽,有明显的共价成分.其吸附能为-43.2 kJ/mol,为化学吸附.结果显示,H2O分子在LiH表面吸附的吸附性质和构型与实验结果一致,并有形成LiOH的趋势.The adsorption mode of H2O molecule on the LiH solid surface, was calculated by the plane-wave ultrasoft pseudopotential method of local density functional theory. The results show that the tilted structure is the optimum adsorption mode and the chemical adsorption energy is - 43.2 kJ/mol, the rotation axis is 37.85°. According to density of states （DOS） before and after the adsorption of H2O, the bond is mainly hybridized by the s and p orbital of LiH with sp^3 orbital of H2O. The bond peak has stronger overlapping characteristic and becomes wider, which reveals that the bond has obvious covalent bonding properties. In conclusion, the adsorption property and structure of H2O molecule on LiH surface agree with experimental results well, and LiH- H2O system has the trend of forming LiOH.

关 键 词：LIH 化学吸附 DOS图 成键 

分 类 号：O552.33[理学—热学与物质分子运动论]