Second order molecular nonlinearities in new orthopalladated push–pull chromophores

Three new orthopalladated chromophores based on push–pull π conjugated ligands have been prepared and characterized. The second order molecular NLO activity has been determined by EFISH measurements giving μgβ values up to 610×10−48 esu at an incident laser wavelength of 1.907 μm. The X-ray structures of two different polymorphs of one chromophore are also reported and polymorphism is discussed in terms of conformational changes.