Influence of the metal atom and the substituents on the third-order nonlinear optical response of some metal dithiolenes

In the present work the influence of the metal atom (Ni, Au, Pt) and the peripheral substituents on the nonlinear optical response of some metal dithiolene complexes are investigated under nanosecond and picosecond, visible and infrared laser pulses. The nonlinear optical properties of the dithiolenes were determined and the values of their second hyperpolarizability were obtained and found to be of the order of 10^-29 and 10^-32 esu under ns and ps laser excitation respectively. The metal atom and the peripheral substituents were both found to affect greatly the nonlinear optical response of the dithiolene complexes.