Specular x-ray reflectivity study of ordering in self-assembled organic and hybrid organic–inorganic electro-optic multilayer films

Specular x-ray reflectivity has been used to probe the microstructures of siloxane-based self-assembled electro-optic superlattices composed of high-hyperpolarizable organic chromophore arrays intercalated with Ga and In oxide sheets. The film thickness increases linearly as a function of the number of layers, underscoring the high structural regularity and efficiency of the synthetic approach. Relatively dense metal oxide structures are detected in these systems. The x-ray reflectivity data also indicate that the dependence of the relative surface roughness on the number of layers is nearly identical for self-assembled organic and organic–inorganic hybrid film structures.