Zhejiang Univ, Dept Phys, Hangzhou 310027, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Synchrotton Radiat Lab, Beijing 100039, Peoples R China
The acetylene (C2H2) adsorbed on Ru(10 (1) over bar0) surface has been studied by using angle-resolved ultraviolet photoelectron spectroscopy (ARUPS). The dependence of the sigma (cc) peak intensity on incidence angle and emission angle shows that C-C axis of acetylene (C2H2) is not parallel to the Ru (10 (1) over bar0) surface (see Fig. 2). The C-C axis of acetylene is tilted in <0001 > azimuth according to its symmetry (see Fig. 3). Not as the acetylene in gas phase, the C-H bond of the acetylene adsorbed on Ru (10 (1) over bar0) surface is not along the direction of the C-C bond.