<title>Nonlinear optical properties of metal-organic complexes with phosphorous-donor ligands</title>

Abstract

Nonlinear optical materials with large intensity-induced changes in refractive index and absorption, which can be characterized by their effective third order susceptibility, are needed for numerous optical device applications. We have reported that Mo(CO)(Ph2PX) complexes exhibit strong, non-resonantly enhanced optical nonlinearities. However, the relationship between the structure of these complexes and their nonlinear optical properties is poorly understood. We have now synthesized Pd(II) and Pt(II) phosphine complexes similar to the Mo(O) complexes and have studied their nonlinear optical properties using Z-scan experiments. The Pd(II) and Pt(II) complexes have a low linear absorption at the working wavelength of 532 nm and exhibit both nonlinear optical refraction and nonlinear optical absorption effects. Our measurements indicate that the nonlinear optical properties of these complexes depend both on the nature of the phosphine ligand and on the nature of the metal center and its coordination geometry. However, this dependence is not as pronounced as we have previously observed in the Mo(CO)(Ph2PX) complexes.