First-principles investigation of a monolayer of C60 on h-BN/Ni„111..

The geometric and electronic structures of a monolayer of C60 on a h-BN monolayer-covered Ni 111 surface are studied by first-principles calculations. The interaction between ions and electrons is described by the projector-augmented plane-wave method. The most stable structure of the h-BN/Ni 111 surface is found to be N on the top and B on the fcc site of Ni 111 . Upon adsorption, the structure in which a hexagon of the C60 molecular is parallel to the substrate is 0.1 eV more favorable in energy than that of a pentagon parallel to the substrate. For the most stable adsorption sites of C60 on h-BN/Ni 111 , the distance between the bottom hexagon of C60 and the h-BN/Ni substrate is 3.6 Å. The calculated results show that the energy differences among different orientations are all smaller than 0.22 eV. No magnetic moment is found for the C60 monolayer. The calculated electronic structures confirm that the h-BN/Ni 111 is a good insulator platform to study the electronic structures of C60 ultrathin films, since only a weak interaction and small charge transfer exist between C60 and h-BN/Ni 111 .