Structural and electronic properties of adsorbed nucleobases on pristine and Al-doped coronene in absence and presence of external electric fields: a computational study

The adsorption of nucleobases (NBs) on pristine and aluminum-doped coronene (Al-coronene) has been studied theoretically using density functional theory (DFT) method in the presence/absence of external electric fields (EFs) having different strengths. The changes in geometric and electronic structures upon the adsorption were analyzed in order to reveal the sensitivity of pristine coronene and Al-coronene toward NBs. The results of theoretical calculations at wB97XD/6–31G(d,p) level of theory showed that the molecular adsorption of NBs on Al-coronene under the external EFs can induce significant change in Al-coronene conductivity. On the basis of calculated changes in band gap energy (Δ E g ) and adsorption energy ( E ads ), it was found that electronic properties of Al-coronene, especially in presence of the applied EFs, are very sensitive to the adsorption of NBs. Finally, electronic structures analysis and full characterization of the surface interactions were performed using the quantum theory of atoms in molecules (QTAIM) to elucidate the nature of NB adsorption interaction. As a result, the enhanced electrical properties of NBs/Al-coronene-adsorbed complexes in the presence of the applied external EFs indicated promising perspectives for fabrication of new NBs-sensing devices.