Theoretical simulation of the third order nonlinear optical properties of some selected organometallics complexes

Theoretical calculations of the third order nonlinear optical coefficient as well as theoretical simulation of UV-VIS absorption spectra for a new alkynyl-ruthenium complexes bearing terminal hydrogen-bonding receptors was presented. The proposed theoretical approach rely on geometry optimisation and corresponding quantum chemical calculations based on semi-empirical ZINDO/1 method within a framework of the restricted Hartree-Fock approach. The theoretically calculated absorption spectral positions are blue shifted in comparison to the experimental spectra for all compounds what is connected with the strong solvent effect. The theoretical calculation show that the second-order hyperpolarizabilities gamma depends from the wavelength of incident electromagnetic radiation. A substitution of the different groups at the end of back side group causes the substantial changes of both absorption spectra as well as nonlinear optical coefficients. We show a dramatic enhancement of the molecular cubic hyperpolarizability in these systems for several wavelength of incident light beam. Comparison of theoretical results with the experimental data is presented.