IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Thursday Sessions
       Session SS2-ThP

Paper SS2-ThP1
Evaluation of Surface Activity using a Molecular Probe

Thursday, November 1, 2001, 5:30 pm, Room 134/135

Session: Beam Interactions with Surfaces Poster Session
Presenter: K. Iizumi, The University of Tokyo, Japan
Authors: K. Iizumi, The University of Tokyo, Japan
K. Ueno, The University of Tokyo, Japan
K. Saiki, The University of Tokyo, Japan
A. Koma, The University of Tokyo, Japan
Correspondent: Click to Email
It is important to investigate activity of various surfaces, since surfaces provide stages where various kinds of phenomena occur. We have examined to evaluate the surface activity through the interaction between C@sub 60@ and the surface. When the surface is active, the interaction between C@sub 60@ and the surface is strong. This strong interaction breaks the high symmetry of C@sub 60@ molecule and modifies its electronic structure. Then the electronic structure of adsorbed C@sub 60@ molecule indicates activity of the surface, onto which C@sub 60@ adsorb. In this sense, a C@sub 60@ molecule can be a good probe to know the degree of activity of the surface. In this paper, we chose three types of surfaces and estimated their activity. These three type of surfaces are as follows; (i) Si(111)-7x7 surface, (ii) dangling bond terminated Si(111) surface: Si(111)-@sr@3x@sr@3-Ag, Si(111)-@sr@3x@sr@3-Ga and Si(111)-1x1-As, (iii) layered material: MoS@sub 2@ cleaved surface. Monolayer C@sub 60@ films were grown on these surfaces and investigated electronic structures of C@sub 60@ by electron-energy-loss (EEL) spectroscopy in the reflection geometry. This is a powerful technique to study surface electronic structures of various materials. EEL spectra of C@sub 60@/Si(111)-7x7 and C@sub 60@/Si(111)-@sr@3x@sr@3-Ga are quite different from that of bulk C@sub 60@. On the other hand, EEL spectra of C@sub 60@/MoS@sub 2@ and C@sub 60@/Si(111)-1x1-As are the same as that of bulk C@sub 60@. The EEL spectrum of C@sub 60@/Si(111)-@sr@3x@sr@3-Ag resembles to that of bulk C@sub 60@. However there is small difference in peak intensities. As a result, we conclude that degrees of activity of above five surface are as follows: Si(111)-7x7, C@sub 60@/Si(111)-@sr@3x@sr@3-Ga >> Si(111)-@sr@3x@sr@3-Ag > C@sub 60@/MoS@sub 2@, C@sub 60@/Si(111)-1x1-As.