O2在NiTi合金(100)表面吸附的理论研究

采用密度泛函方法应用赝势基组对NiTi合金（100）表面的电子结构以及氧分子（O2）的吸附和解离过程进行了系统研究．结果表明，Ti原子裸露表面比Ni原子裸露表面反应活性高，02吸附为活化解离吸附，顶位吸附结构最不稳定，易向桥位或洞位吸附转化，桥位吸附对应的吸附结构最为稳定．态密度分析和结构分析表明，氧原子与表面的相互作用主要是由氧原子价轨道和NiTi合金杂化表面轨道贡献．

First principle study of O2 adsorption on NiTi alloy (100) surface

First principle pseudopotential plane wave calculations based on density functional theory and the generalized gradient approximation (GGA) have been used to study the electronic structure of NiTi (100) surface, adsorption and decomposition of O2 on the NiTi alloy (100) surface. The results show that Ti-terminated surface is more reactive than Ni-terminated surface. O2 is activated and will decompose after adsorption. Among several possible adsorption configurations considered, the most stable one corresponds to bridge configuration and the top configuration is unstable. Analysis of the structure and density of state (DOS) shows the interaction of oxygen atom and surface results mainly from the total contribution of valance orbital of oxygen atom and hybridized surface orbital of NiTi alloy.