Chelations of neutral and one–electron positive ionic alkali metals including Lithium (Li/Li+), Sodium (Na/Na+) and Potassium (K/K+) by 3–Hydroxy–4–Pyridinone (HPO) have been investigated by the in silico density functional theory (DFT) approach. The investigated single HPO and corresponding complex systems have been first optimized and their properties have been then evaluated for the minimized energy structures. Moreover, the atomic scale quadrupole coupling constant (QCC) properties have been evaluated for further investigations of the optimized complex systems. The results indicated that the neutral/ionic states of alkali metals are important for determining the complex systems in addition to their element types. Moreover, the effects of chelations on molecular orbitals could propose complex systems for different diagnostics activities. The atomic scale properties also indicated that all atoms of complex systems are important for chelation processes. And finally, the HPO structure could be proposed for alkali metal chelation with differential diagnostic activities.