Electronic and structural properties of C59Si on the monohydride Si(100) surface

We propose the use of the Si atom in the C 5 9 Si molecule as a possible way to controllably anchor fullerene molecules on an Si surface, due to the formation of a strong bond to one of the Si surface atoms. We considered a monohydride Si(100) surface with the H removed from one of the Si surface atoms, and the C 5 9 Si was adsorbed at this site. Through ab initio calculations based on Density Functional Theory, we obtained a final Si s u r f a c e -Si C 5 9 S i bond distance of 2.37 A, and a binding energy of -3.0 eV. Considering the reaction H s u r f a c e + C 5 9 SiH → (C 5 9 Si) a d s o r b e d + (H 2 ) g a s , we find this process to be exothermic by 0.41 eV. Upon adsorption of an isolated molecule, we find four levels in the gap, three empty and one singly occupied, all of them being basically localized at the C 5 9 Si molecule.