Abstract
A method has been developed for analysing the fractal surface behaviour of 8- (hydroxyquinoline)zinc (Znq2) using small-angle X-ray scattering (SAXS). The measurements indicated that the surface of Znq2 can be described by fractal and powerlaw decay of the scattering intensity I for values of the scattering vector q between 0.8 nm-1 and 5 nm-1 where I(q) ~ qα. The exponent is smaller than the four values given by Porod's law. The surface fractal dimension Ds was found to be 2.96 in agreement with surface fractals. We also report the fractal surface characteristics of 8- (hydroxyquinoline)aluminum (Alq3) and make a comparison between the fractal surface behaviours of Znq2 and Alq3. We believe that SAXS is the most appropriate technique for the determination of the fractal dimension and that it can be used to study the relations between the surface and electro-optical properties of organic materials.