周期性密度泛函理论研究NO在CuCl(111)表面上的吸附

A DFT Study on the Adsorption of NO over CuCl(111) Surface

运用广义梯度密度泛函理论(GGA)的RPBE方法结合周期平板模型,在DNP基组下,研究了NO以N端和O端两种吸附取向在CuCl(111)表面上的吸附.通过对不同吸附位和不同覆盖度下的吸附能和几何构型参数的计算和比较发现:NO吸附在CuCl(111)表面Cu原子上的top位时为稳定的吸附;覆盖度为0.25 mL时吸附比较稳定;NO的N端吸附比O端吸附更有利,N端吸附时为化学吸附,O端吸附时为物理吸附.布居分析结果表明整个吸附体系发生了从Cu原子向NO分子的电荷转移,且O端吸附时电荷转移更多.N端吸附和O端吸附时,N-O键的伸缩振动频率均红移,同时O端吸附时红移更多.

The adsorption of NO molecule on CuCl （ 111 ） surface has been studied with periodic slab model by RPBE approach of GGA within file framework of density functional theory （DFT）. Two molecular orientations, N- end and O-end, over various adsorption sites, top, hollow, bridge and Cl site of CuCl （ 111 ） surface have been considered. Two molecular orientations under different coverage of CuCl （ 111 ） surface also have been considered. The optimized results indicate that the N-end adsorption models are more stable than the O-end ones. The adsorption of N-end modes over CuCl （ 111 ） surface are chemisorption while the adsorption of O-end modes over CuC1 （ 111 ） surface are physical adsorption. The N-O stretching vibrational frequencies are significantly red-shifted upon coordination for N-end. The population analysis indicates that the charges transfer from Cu atoms to NO molecule.