Probing nonlinear optical properties of nanoparticles and supramolecular assembles by third-harmonic Rayleigh scattering

In this report we capitalize on this intriguing finding to study molecular structures and assemblies in solutions. By measuring the power of the third-harmonic generated in a solution of nanoparticles, we determined both the size and the third-order nonlinear optical susceptibility of those nanoparticles. The newly developed technique was successfully employed to observe the structural organization of collagen (type I) molecules in solution.