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.