We perform a classical molecular dynamics simulation, a first-principle calculation based on LDA, and moreover a simple theoretical analysis to examine the very interesting crystalographic structure of the first layer and overlayer C60s adsorbed on the As-rich substrate of the GaAs(001) surface, which was recently observed with the STM by our group. From the classical molecular dynamics study, we reproduce the pairwise structure of C60 adsorbed in the first layer. On the other hand, from the first-principle study, we estimate how much the charge transfer is from the underlayer As atoms to the C60s adsorbed in the first layer. We found that the amount of this charge transfer is large enough to expect that the strong dipole field caused by this dipole layer at the interface induces dipole moments in the C60s adsorbed on overlayers and that the resulting dipole-dipole interaction among the overlayer C60 molecules is the origin of the 13% lattice expansion of the overlayer C60 fee thin film observed experimentally.
|Number of pages||5|
|Journal||Science Reports of the Rerearch Institutes Tohoku University Series A-Physics|
|Publication status||Published - 1997 Dec 1|
- Numerical simulation
ASJC Scopus subject areas
- Condensed Matter Physics
- Metals and Alloys