乙烯在Ni（110）表面吸附的几何结构

用理论计算的方法研究了不同覆盖度的乙烯在Ni（110）表面吸附的位置.乙烯的吸附几何结构在团簇计算中进行了局部优化.在低覆盖度下，单个乙烯分子占据了短桥位和顶位之间的中间位置.乙烯分子的C—C轴大致沿衬底的Ni原子链排列（即沿<110>晶向），C—C轴与衬底Ni（110）表面有10°的倾斜角.乙烯分子的C—C键的键长为0151nm.在高覆盖度下(05ML)，乙烯在Ni (110)上形成了有序的c（2×4）相，在一个表面元胞内的两个乙烯分子的吸附位置类似于低覆盖度时的结果，但乙烯分子的C—C 键键长分别为0142和0143nm.

The adsorption geometry of ethylene on the Ni (110) surface

The favourite adsorption site of ethylene on the Ni (110) surface at high and low coverages was investigated by theoretical calculation. In the cluster calculations a partial optimization of adsorbate geometry has been carried out. At low coverage the ethylene molecule occupies approximately the midway between the short-bridge and atop sites. The C—C axes of molecules are almost parallel to the ridges and are offset in the <110> direction, the angle of C—C axis with respect to the Ni surface plane is about 10°. The C—C bond length is 0151 nm. At a high coverage (05ML), ethylenes form a c (2×4) phase. The local adsorption sites of two ethylene molecules in a surface unit mesh are found to be quite similar to that at low coverage, but the C—C bond lengths are 0142 nm and 0142 nm, respectively.