Third order nonlinearity in organometallic polyalkynes

Polymeric materials made of polyalkynes [-C≡C-]_n have long been known to exhibit delocalized π-electron systems. However. these materials normally are insoluble and hence of little practical use as nonlinear optical materials. We have prepared a series of polyalkynes which incorporate side chains, typically attached to a metal atom such as Pt. causing the polymer to be readily soluble. The rigid-rod geometry of ordinary polyalkynes is preserved in this arrangement due to the square planar coordination of the metal atom. The thermal stability (decomposition temperature and T_g) measurements and the third-order nonlinear susceptibilities determined at 1064 nm are presented.