Dynamic Analysis of Adsorption-Desorption Equilibrium of Sublimed Aromatic Molecules Using Polarized Optical Waveguide Spectroscopy

The adsorption-desorption equilibrium of sublimed molecules has been analyzed dynamically by optical waveguide (OWG) spectroscopy. Dynamic change of the transition moment during adsorption behavior was successfully detected using polarized incident light. With this technique, sublimed planer aromatic molecules, such as azobenzene, were revealed to stack parallel to the solid surface at the initial stage followed by adsorption with relatively random orientation.