Relaxations of methylpyridinone tautomers at the C60 surfaces: DFT studies

Abstract

Density functional theory (DFT) based calculations have been performed to examine the relaxations of tautomers of 4–hydroxy–6–methylpyridin–2(1H)–one (MPO), as a representative of pyridinone derivatives, at the fullerene (C₆₀) surfaces. Optimized molecular properties including energies, dipole moments and atomic scale quadrupole coupling constants (<em>C</em>_Q) have been evaluated to investigate the structural and electronic properties of the models. The structural configurations of tautomers show different relaxations at the C₆₀surface yielding different magnitudes of total and binding energies. Moreover, deformation of each tautomer due to relaxation at the C₆₀surface with respect to the initial singular structure has been examined. Complimentary parameters of energy gaps and dipole moments exhibit the effects of relaxations at the C₆₀surface for the MPO counterparts. Atomic scale <em>C</em>_Q properties also indicate that the electronic properties of atoms show significant changes for tautomers and hybrid systems. As a final note, the tautomeric structures in singular and hybrid forms exhibit different electronic properties because of effects of interactions with C₆₀, especially for the interaction regions.