Benzene adsorption on Ir{100} studied by low-energy electron diffraction I-V analysis;Evidence for formation of tilted benzyne

摘要

In order to increase undestanding of the structure and bonding of aromatic molecules and their fragments on transition metal surfaces,a low-energy electron diffraction(LEED) study of benzene adsorptionon Ir{100} has been carried out.Following benzene adsorption at 465K,ac(2*4)LEED pattern is observed.Its formation is accompanied by the loss of two hydrogen atoms as H_2,indicating that benzyne (C_6H_4) is formed.This is the first time an ordered overalyer of benzyne has been observed on a transition metal surface.It makes the structue accessible to LEED I-V analysis,providing the most reliable structural information for benzyne adsorbed on a transition metal surface todate.The benzyne species was found to be di-#delta# bonded to the bridge wite with a 47degC tilt angle to the surface normal.