Extended conjugation and its effect on the third-order nonlinearities of charge transfer chromophores

This article investigates a series of donor-acceptor chromophores that show an extraordinarily large third-order optical nonlinearity compared to their molecular size. With these compounds, the authors are able at the same time to approach the fundamental limit for the molecular third-order polarizability within about an order of magnitude and to obtain very large specific third-order polarizabilities.