Large optical-limiting response in some solution-processable polyplatinaynes

Experimental investigations of the nonlinear optical transmittance characteristics of a series of solution-processable platinum polyyne polymers at 532 nm show that they are excellent optical limiters with performance comparable or superior to those of the state-of-the-art reverse saturable absorption dyes such as fullerene C₆₀ and metal phthalocyanine complexes. On the basis of results from photophysical studies, both the inclusion of a platinum chromophore for increasing the intersystem crossing rate and the formation of an intramolecular charge-transfer state between the electron-withdrawing and electron-donating moieties along the polymer chain are very effective approaches for the enhancement of the optical-limiting properties of these metal polyynes. The structural influence of the aryl linker units on the optical-limiting action has been evaluated in detail. The optical-limiting thresholds for these polymetallaynes range from 0.06 to 0.15 J/cm² at 82% linear transmittance, and these polymeric materials are very promising candidates for use in practical optical-limiting devices.