AVS 47th International Symposium
    Processing at the Nanoscale/NANO 6 Monday Sessions
       Session NS+NANO6-MoA

Paper NS+NANO6-MoA10
Adsorption and Manipulation of Endohedral Fullerenes on Silicon Surfaces

Monday, October 2, 2000, 5:00 pm, Room 302

Session: Manipulation of Atoms and Molecules
Presenter: P.H. Beton, University of Nottingham, UK
Authors: M.J. Butcher, University of Nottingham, UK
P.H. Beton, University of Nottingham, UK
P. Kuran, IFW Dresden, Germany
L. Dunsch, IFW Dresden, Germany
Correspondent: Click to Email
The adsorption and manipulation of an endohedral fullerene, LaC82 has been investigated using a scanning tunnelling microscope (STM) operating at room temperature in ultra-high vacuum. These molecules are adsorbed on top of both rows and troughs on the Si(100)-2x1 surface, and like C60 may be manipulated in a repulsive mode using the STM tip. However for LaC82 a much stronger interaction between adsorbate and tip is required to promote manipulation resulting in a lower voltage threshold for this process. Adsorption of this species on a less reactive substrate (for example, Ag/Si(111)) results in the formation of close packed hexagonal islands oriented, primarily, parallel to the principal axes of the Si surface. This result confirms an expected commensurability of the intermolecular spacing, d, and the surface lattice constant, namely d~3a, indicating that it should be possible to form close packed rows of LaC82 along the troughs of Si(100)-2x1. The formation of pairs and other simple close packed assemblies of molecules has been demonstrated. A comparison of the response to manipulation of a range of fullerenes and heterofullerenes will also be presented and discussed in terms of the effects of size and chemistry of the adsorbed molecules.