Interaction between Al and graphene. Density functional study of adsorption and insertion processes.

NICOLÁS F. DOMANCICH; RICARDO M. FERULLO; NORBERTO J. CASTELLANI

Encuentro; NanoCórdoba 2012; 2012

In the present work a molecular orbital calculation was performed with a local basis set and within (DFT) in order to study the adsorption of an Al atom on regular sites and on a C vacancy of graphene. In this way we are able to compare with the same model the results obtained with the PBE and B3LYP functionals. While the results are largely dependent on the functional used for the adsorption on regular sites, they show the same behaviour with both functionals for Al adsorbed on the monovacancy. On the regular graphene surface, the B3LYP results indicate that at Al-graphene distances around 2.2 Å an important repulsion is present, related to electronic exchange-correlation effects. Complementary calculations carried out at MP2 level show that at large distances the dispersive forces produce the presence of binding states, not predicted by DFT, thermodynamically favoured by about 0.2 eV.