Abstract
A measurement system for resonant second harmonic(RSH) spectroscopy using an optical arrangement of total internal reflection was developed as an analytical method for investigating molecules adsorbed on substrate surfaces. RSH spectra were measured for the rhodamine B molecules adsorbed on a fused quartz substrate with different coverages. It was demonstrated for the first time by the polarization measurements that aggregation of rhodamine B occurred on a fused quartz, and that both of the dimeric and monomeric species coexisted on the surface.