Graphene oxide nanosheet: A DFT Study of NMR and NQR parameters

In order to investigation of the properties of the electronic structure of Graphene Oxide nanosheet, density functional theory calculations are performed at the level of the M05-2X method in combination with 6-31G* basis set using Gaussian 03 package program. Calculated electric field gradient tensors are used to determine the 17O and 13C nuclear quadrupole coupling constant, CQ and asymmetry parameter, η. For better understanding of the electronic structure of the nanosheet, isotropic and anisotropic NMR chemical shieldings are calculated for the 13C and 17O nuclei using GIAO method. The results reveal that the calculated chemical shieldings and NQR parameters do not indicate a regular pattern for carbon nuclei of Graphene oxide nanosheet. These different values must arise from differences in the surrounding environment of these atoms due to bonding to various functional groups.