Crystal growth and characterisation of the electro-optic material 3-(2,2-dicyanoethenyl)-1-phenyl-4,5-dihydro-1H-pyrazole

The growth of 3-(2,2-dicyanoethenyl)-1-phenyl-4,5-dihydro-1H-pyrazole crystals from toluene and ethyl acetate solutions is described. Kinetic data indicate the development of a polar morphology due to anisotropic solvent adsorption. A double-solvent technique has been used to grow crystals up to 1 cm2 in cross-section and their perfection was examined by X-ray section topography.