▎ 摘　　要

Quercetin (3,5,7,3', 4' -pentahydroxyflavone) is a member of flavonoids. Density functional theory has been employed to study the adsorption of quercetin on single layer graphene (QCT-SLG) was investigated with the basis set of 6-21G. The total density of states and partial density states of the titled molecules were performed at density functional theory method. The molecular electrostatic potential (MEP) mapping shows the binding interactions of quercetin with single graphene layer. Dipole moment, hyperpolarizability and quantum chemical parameters have been calculated by Hartree Fock (HF) approximation approach. The natural bonding orbital analyses (NBO) calculation confined that the occurrence of intramolecular charge transfer takes place within the molecules. From DFT, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of frontier orbital were obtained.