New insights into electronic and adsorption energies of metallofullerenes C19M

A comprehensive electronic investigation was carried out by G09W program to provide new insights into the adsorption energies of metallofullerenes C19M (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn). In this regard, the DFT calculations were performed on the geometric, electronic, and thermodynamic properties of ten metallofullerenes C19M cages and twenty Favipiravir/Oseltamivir metallofullerene complexes. The results showed that there is an excellent linear relationship between the adsorption energies of Favipiravir/Oseltamivir drugs and the dipole moments, HOMOs and energy gaps of C19M cages. Moreover, the C19Sc and C19Ti cages characterize by their high dipole moments, small band gaps and closest HOMOs energies to those of LUMOs energies of Favipiravir/Oseltamivir drugs. Finally, the calculated thermodynamic parameters (ΔH and ΔG) for Favipiravir/Oseltamivir metallofullerene complexes were found to have negative energies, reflecting the stability of Oseltamivir/Favipiravir C19M complexes. Accordingly, this study provides the necessary/useful background information for the design of nanomaterials for better drug delivery

On the spectroscopic analyses of thioindigo dye

Highlights: [•] B3LYP as well as FTIR were utilized to analyze thioindigo dye. [•] Vibrational assignments for thioindigo isomers were aided at B3LYP/6-311G(d,p). [•] Cis-isomer is a promising structure for optoelectronic devices as solar cells. [•] Cis-isomer has a high dipole moment (3.44 Debye) and HOMO/LUMO energy gap (3.02 eV)

First-principle study of magnetism induced by vacancies in graphene

Spin-polarized density functional theory has been used to study the effects of vacancy defects on the magnetic properties of graphene. Structural optimization shows that introducing a carbon vacancy cluster into a graphene sheet changes the spatial distribution of the neighbor atoms, particularly those located around the vacancy. From spin-polarized DOS and LPDOS calculations, we find that only vacancies containing unpaired electrons show magnetism. These results lead us to formulate a relation between the vacancy-induced magnetic moment and the size and shape of the vacancy clusters in graphene sheet. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2011