Investigating an iron-doped fullerene cage for adsorption of niacin (vitamin B3): DFT analyses of bimolecular complex formations

•A representative model of iron (Fe)-doped fullerene cage (Cage) was investigated for adsorbing the niacin (Nic) vitamin B3 component.•Density functional theory (DFT) calculations were performed and the results indicated three possible configurations of Cage-Nic bimolecular complexes.•The features of quantum theory of atoms in molecules (QTAIM) were analyzed.•The illustrated diagrams of density of states (DOS) indicated benefits of employed Cage for sensor function of the adsorbed Nic component.