Optical properties of poly(para-phenylenes) under high pressure

Abstract

We present optical studies using photoluminescence, absorption and Raman scattering on samples from two generic families, the polycrystalline para-phenylene oligomers and the amorphous paraphenylene polymers, under hydrostatic pressure. These studies have provided insight into the geometry of the molecules, and the fundamental properties of the ground and excited states of these materials. Using our measurements under pressure and a simple model we extract atmospheric pressure values for the shift in the configuration coordinate between ground and excited states and the ratio of force constants describing the potential wells that describe these states.