CAJ | 학술논문

本文采用第一性原理和周期平板模型相结合的方法,对甲氧基在 Ir(111)表面 top,bridge,fcc 和hcp位的吸附模型进行了构型优化、能量计算、Mulliken电荷布居分析以及差分电荷密度计算.结果表明,甲氧基通过氧原子与金属表面相互作用时,垂直吸附在 fcc位是最有利的吸附构型,吸附能为2.26 eV,此时电子从金属表面向甲氧基转移.吸附过程中C-O键振动频率发生红移,表明在该表面 C-O 键容易被活化.结合差分电荷密度分析表明,吸附时CH3 O中氧的2p原子轨道和铱的 dz2原子轨道相互作用形成σ键.
본문채용제일성원리화주기평판모형상결합적방법,대갑양기재 Ir(111)표면 top,bridge,fcc 화hcp위적흡부모형진행료구형우화、능량계산、Mulliken전하포거분석이급차분전하밀도계산.결과표명,갑양기통과양원자여금속표면상호작용시,수직흡부재 fcc위시최유리적흡부구형,흡부능위2.26 eV,차시전자종금속표면향갑양기전이.흡부과정중C-O건진동빈솔발생홍이,표명재해표면 C-O 건용역피활화.결합차분전하밀도분석표명,흡부시CH3 O중양적2p원자궤도화의적 dz2원자궤도상호작용형성σ건.
The first-principles density functional theory (DFT)and the periodic slab model are used to investigate the adsorption of methoxy on Ir (111)surface.The adsorption energies,equilibrium geome-try,Mulliken charges and charge density difference are calculated.The results show that methoxy ad-sorbs at the fcc site vertically via the oxygen atom with the adsorption energy of 2.26 eV.The electronic charges transfer from Ir to methoxy species.The stretching frequency for C-O bond of CH3 O has a red shift,which indicates that the C-O bond is easy to be activated.According to the analysis of the charge density difference,the 2p atomic orbits of oxygen interact with the dz2 orbit of iridium atoms to form theσorbit in bonding.