Adsorption of Pyrimidin-2-amine (PA) on Graphene Quantum Dots (GQDs): Non-covalent Interaction Study

A detailed theoretical study was implemented on a novel drug molecule “Pyrimidin-2-amine (PA)”. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) simulations were accomplished to explain the adsorption performance of the PA drug molecule on graphene quantum dots (GQD). Binding and adsorption energy, 4-energy molecular orbitals analysis, charge transfer effect, QTAIM, dipole moment, NLO properties, frontier molecular orbital analysis (FMO), the density of states (DOS), RDG-isosurfaces, UV–Visible, and SERS spectra analysis have been explored while performing the DFT simulations. The total adsorption energy of PA was calculated to be −3.45, –22.48, −20.32, −3.78, and −4.47 Kcal/mol for the corresponding CC-PA, BB-P-PA (where “P” stands for the para position of doped elements), NN-P-PA, BN-O-PA (where “O” stands for the ortho position of doped elements), and BN-P-PA complexes respectively. The intermolecular interaction forces were dogged by the establishment of numerous bond critical points (BCPs), monitored by ring critical points (RCPs) at the midpoint of the interaction state.