ORIENTATION OF NICKELOCENE ON AG(100)

High-resolution electron-energy-loss spectroscopy has been used to stu dy the molecular adsorption of nickelocene, Ni(C5H5)(2), on Ag(100). R esults indicate that at up to one monolayer coverage, nickelocene adso rbs molecularly with its axis approximately perpendicular to the surfa ce. At very high coverages, the molecular axis is not exclusively orie nted along the surface normal. This is possibly due to randomization o f the metallocene orientation as multilayers are formed. (C) 1998 Else vier Science B.V. All rights reserved.