We use optical Second Harmonic Generation (SHG) to probe different kinds of surface properties of dispersed particle systems in in-situ and in real time. Examples for applications are the direct study of molecular adsorption at particle surfaces and the determination of surface potentials of colloids. The focus of this paper is on the application of the SHG technique on complex and technically highly relevant systems. In this context we will discuss aspects of practical relevance such as the influence of the detection geometry and the dependence of the SH scattering process on particle concentration and particle size distribution. Further, we present a novel nonlinear Mie Theory that is capable to simulate the SH scattering from individual molecules with arbitrary orientation that are located at the surface of spherical particles. Finally, we will show that the new theory can be used to determine the orientation of adsorped surfaces molecules from angle-resolved SHG experiments.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2010: Advanced Materials, CNTs, Particles, Films and Composites
Published: June 21, 2010
Pages: 33 - 36
Industry sector: Advanced Materials & Manufacturing
Topics: Materials Characterization & Imaging