RESUMO
We have performed a Density Functional study of the CO adsorption in B-doped, N-doped and BN-co-doped graphene considering a coronene based model in order to estimate the applications of this systems as CO-sensor. Different monosubstituted, disubstituted and trisubstituted alternatives of combining these two heteroatoms in a substitutional chemical doping and the influence of the relative positions of the heteroatoms are analyzed. In this study, the stability selectivity for CO adsorption and the change in the electric properties for the presence of this molecule, have been evaluated through the calculation of binding energy, CO-adsorption's energy and the gap HOMO-LUMO change due to CO adsorption. The results indicated that, even though all the configurations were stables and was confirmed a CO physical adsorption in all of them, the relative positions of Nitrogen and Boron gave different stabilities and different responses to the CO adsorption. Since monosubstituted Boron-coronene was the second in stability respect to pristine coronene, showed the highest CO adsorption energy and was also the second highest ∆(∆HOMO-LUMO) value, this structure could be potentially a good CO-sensor.
RESUMO
Density functional theory optimized basis sets for gradient corrected functionals for 3d transition metal atoms are presented. Double zeta valence polarization and triple zeta valence polarization basis sets are optimized with the PW86 functional. The performance of the newly optimized basis sets is tested in atomic and molecular calculations. Excitation energies of 3d transition metal atoms, as well as electronic configurations, structural parameters, dissociation energies, and harmonic vibrational frequencies of a large number of molecules containing 3d transition metal elements, are presented. The obtained results are compared with available experimental data as well as with other theoretical data from the literature.