An ab initio study of metalated CMP,UMP& dTMP at HF level:Bond energies and isotropic NMR shielding of atoms

The interaction of Magnesium hydrate at the phosphate oxygen atom of the pyrimidine nucleotides (CMP,UMP,dTMP) were studied at the Hartree-Fock level Theory. We used LANL2DZ basis set for Mg and 6-31g* basis set for atoms.The basis set superposition error (BSSE) begins to converge for used Method/basis set. The gauge-invariant atomic orbital (GIAO) method and the continuous-set-of-gauge-transformation (CSGT) procedure were employed to calculate isotropic atomic shielding of the nucleotides using density functional theory at the B3LYP/6-31g** . These calculations yield molecular geometries in good agreement with available experimental data.