FIELD-INDUCED MANIPULATION OF FULLERENE MOLECULES WITH THE STM - A SELF-CONSISTENT THEORETICAL-STUDY

By applying an appropriate voltage between an STM tip and a metallic s ubstrate, it is possible to induce highly localized electrostatic fiel ds. In this paper, it is shown that the apex of the STM probe, respons ible for the resolution, confines an electric field of small lateral e xtension inside the junction. The change in the potential energy of an adsorbate submitted to such a field is calculated with a self-consist ent scheme. A microscopic description of both the tip-apex and the ads orbates is used and the correlations between each polarizable centre a re accounted for with a discretized Lippmann-Schwinger equation. Sever al applications show that our real space approach is extremely attract ive for studying electrostatic field distributions in low symmetry sys tems. Field induced manipulation processes of C-60 molecules are discu ssed in this context.