Correlation between Pressure-Induced Optical Shifts and Compressibilities of Polymers Doped with Dye Molecules

Using the high spectral resolution of the hole burning technique under hydrostatic-pressure conditions, we report a correlation between optical and mechanical data. The shifts of optical transitions of dopant molecules in polymers can be measured at pressures as low as 100 hPa. We derive low-temperature compressibilities close to the mechanically measured values. This agreement is based on a R -6 -dependence of the solvent shift as postulated for nonpolar molecules in nonpolar hosts.