III Vibrational Investigations of Rubbed Surfaces.

This project is developed in collaboration with the group of Prof. R.Shen (UC Berkeley, USA). In order to characterize the extreme surface of rubbed polymers, we are using a variety of ultrasensitive techniques to measure the orientation of specific chemical groups. Linear spectroscopies such as Raman and PM-IRLD (Univ. Bordeaux) are surface specific, but polarization measurements help to discriminate molecular orientation at the interface. Sum Frequency Generation spectroscopy (UC Berkeley) is ideal since it is mainly sensitive to surfaces and interfaces where the centrosymmetry of the material is necessarily broken.