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对于氢原子定位于Ti_4,Ti_5,Ti_(17)和Ti_(20)等钛原子簇的问题,应用推广的Huckel 分子轨道(EHMO)理论进行了研究。与前人所作从头算的结果一致,发现氢原子在完全晶体的外部三重配位的位置上优于内部各处。而在钛原子簇内又是四面体环境优于八面体环境.氢原子在内部各处时的结合能.还因为邻近空穴的存在增大.较之表面位置而言,确实只有与空穴相邻的四面体位置是唯一稳定的内部环境。Ti_(17)的态密度图表明,由氢而产生的带位于Fcrmi 能级下约6.5ev 处,光电子发射的结果是定性相符的.
The hydrogen atom localization in the Ti_4, Ti_5, Ti_ (17) and Ti_ (20) cluster of titanium atoms was investigated using the extended Huckel molecular orbital (EHMO) theory. Consistent with the results of previous studies, it has been found that hydrogen atoms outperform the interior of the crystal at the positions where external triplet coordination of the crystal is complete. In the titanium atom cluster is a tetrahedral environment is better than the octahedral environment.Hydrogen atoms in the internal binding energy.Because the presence of adjacent holes increases.Compared with the surface position, and indeed only holes Adjacent tetrahedral sites are the only stable internal environment. The state density diagram of Ti_ (17) shows that the band produced by hydrogen is located at about 6.5ev below the Fcrmi level and the photoelectron emission results are qualitatively consistent.