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

The optical properties (both linear and nonlinear) of a series of conj ugated group 10 transition-metal (Ni, Pd, and Pt) organometallic syste ms have been studied. A strong dependence of the maximum absorption wa velength (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 whi ch are remarkably large and compare very well with analogous organic s ystems such as polydiacetylene or polythiophene. The established trend s in optical properties have led to a good understanding of the nature of the interaction of metal with organic system in this family of com pounds in the nonlinear regime.