苯分子在Cu(100)面平板模型上吸附的密度泛函理论研究

使用量子化学中的密度泛函理论和平板周期模型方法，研究了苯在Cu(100)面上的吸附方式和相对稳定性. 计算结果表明，苯在Cu(100)表面的吸附属于较强的化学作用，稳定性穴位优于桥位，顶位吸附最不稳定. 在吸附过程中，C—C键有相对大的伸长，C—H键的键长变化较小，但是偏离苯环平面，并背离固体表面，顶位则是朝向表面. 吸附过程中，发生了电子从苯向铜原子的转移.

A Density Functional Study of Benzene Adsorption on Cu(100) Surface

The adsorption of benzene on Cu(100) was analyzed using the first-principle density functional theoretical (DFT) slab calculation. In three optimized adsorption modes the benzene molecules were parallel to the surface and the carbon rings were distorted. The calculated results showed that interaction between the substrate and benzene molecule was relatively strong chemisorption. The hollow site was the most favorable adsorpion site of benzene on Cu(100) surface, followed by the bridge one. The top site was the least stable. The C—C bond was elongated in comparison with the free benzene molecule while the variation of C—H length was small. The hydrogen atoms bent away from the solid surface, but they bent toward the solid surface in the top site. Electron transference was found from benzene to Cu substrate.