LINEAR AND 3RD-ORDER NONLINEAR-OPTICAL PROPERTIES OF ONE-DIMENSIONAL ORGANOMETALLIC SYSTEMS

The optical properties (both linear and nonlinear) of a series of conjugated group 10 transition-metal (Ni, Pd, and Pt) organometallic systems have been studied. A strong dependence of the maximum absorption wavelength (lambda(max)) on metal centre for a fixed conjugated organic system is observed in the visible absorption spectrum. The same trends are observed for the values of second molecular hyperpolarisability (gamma) measured using forward degenerate four wave mixing at 1.064mum. A strong dependence of gamma on conjugated organic system for a fixed metal is also observed. Larger organometallic polymeric systems have been shown to possess large second molecular hyperpolarisabilities which are remarkably large and compare very well with analogous organic systems such as polydiacetylene or polythiophene. The established trends in optical properties have led to a good understanding of the nature of the interaction of metal with organic system in this family of compounds in the nonlinear regime.