NMR and natural bond orbital (NBO) calculation of glyoxals: Nano physical parameter investigation

Abstract

In this article, six theoretical methods have been used for calculation of physical parameters in five derivatives of glyoxals. We calculated physical parameters like atomic charges, energy (ΔE), chemical shift anisotropy (δ), asymmetry parameter (η), chemical shift anisotropy (∆σ), dipole moment, isotropic, anisotropic, NMR determinant and distance matrix determinant. In this work, we used Gaussian 98 at NMR and natural bond orbital (NBO) calculation by using HF method with 6-31G, 6-31G*, 6-31+G basis set and B3LYP, BLYP and B3PW91 methods with 6-31G basis set. GIAO magnetic shielding for studied molecules was obtained using Gauss view program. Chemical shift curve was drawn for all of the atoms in each molecule.