【摘要】 采用密度泛函方法 ,以原子簇Cu14 为模拟表面 ,对氢氰酸 (HCN)和异氰酸 (HNC)在Cu( 10 0 )表面上不同吸附位的吸附情况进行了研究 .结果表明 :HCN和HNC分别通过原子N和C垂直吸附在表面上时 ,顶位是其最佳吸附位 ,且是吸附能为 18 5kJ·mol-1和 42 6kJ·mol-1的弱吸附 ,计算结果与实验相符 .C—N(HCN)键或N—C(HNC)键偏离垂直的分子轴线的吸附体系均不稳定 .顶位吸附时HCN和HNC分子的C—N键振动频率均发生蓝移 .更多还原

【Abstract】 The interaction of HCN and HNC with the different sites of Cu(100) surface is studied by using density functional theory (DFT). Cu 14 cluster is used to simulate the surface. The present calculations show that HCN and HNC bind to the surface in an end on geometry with the molecular axis perpendicular to the surface and adsorption on top site is prefered with the adsorption energy of 18 5 kJ·mol -1 and 42 6 kJ·mol -1 , a weak adsorption in accordance with the experimental results. Tilting either the C-N bond or the N-C bond away from the surface destabilizes the system. After adsorption, the calculated C-N stretching frequencies are blue shifted for end on bonded HCN and HNC on top of Cu(100).更多还原