Résumé:
In this work, we report a theoretical study on molecular structure, electrostatic potential and nonlinear optical properties of Zwitterionic 6-methyl-2-oxo-3-[1-(ureidoiminio)ethyl]-2H-pyran-4-olate monohydrate molecule (monomer and dimer ). The molecular geometry in the ground state was investigated by ab initio and density functional method (B3LYP) with 6-31G(d) and 6-31+G(d,p) basis sets. The results show that the computed geometrical parameters are in good agreement with experimental values. The molecular electrostatic potential and HOMO-LUMO of the title molecule have been also calculated using the theoretical methods. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. In order to investigate the nonlinear optical behavior, the electric dipole moment , the polarizability and the hyperpolarizability were computed. All values that we report here are the magnitude of static hyperpolarizability. Theoretically predicted values exhibit the higher nonlinear optical activity.