We present density-functional theory calculations of the adsorption of ${\text{C}}_{60}$ on the $\text{Si}\left(111\right)\text{-p}\left(7\times 7\right)$ surface. We have considered seven different adsorption configurations, including the corner hole and other adsorption sites with a high degree of coordination with the dangling bonds of the surface. Tight-binding molecular dynamics suggest that the highly reactive adatoms and rest atoms of the $\left(7\times 7\right)$ reconstruction are always able to adjust the ${\text{C}}_{60}$ position—rotating it and displacing it—so that one of such adsorption configurations is possible. We have then performed scanning tunneling microscopy and scanning tunneling spectroscopy simulations of the adsorbed geometries, taking explicitly into account the tip, i.e., beyond the Tersoff-Hamann approach, and considering both a Pt and a W tip structure.

• Received 15 September 2009

DOI:https://doi.org/10.1103/PhysRevB.81.075419