Cu(100)表面吸附HCN和HNC的密度泛函研究  

Study of HCN and HNC Adsorption on Cu(100) by Density Functional Theory

作　　者：胡建明[1] 李奕[1] 李俊篯[1] 章永凡[1] 周立新[1] 

机构地区：[1]福州大学化学化工学院

出　　处：《化学学报》2003年第4期476-480,共5页Acta Chimica Sinica

基　　金：国家自然科学基金 (Nos.2 99730 0 6 ;2 0 2 730 1 3);福建省自然科学基金 (No.E0 1 1 0 0 1 1 )资助项目

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 .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).

关 键 词：表面吸附 HCN HNC 密度泛函 氢氰酸 异氰酸 蓝移 过渡金属 铜 

分 类 号：O647.3[理学—物理化学]