Free Volume Nanocavities in PMMA Revealed by Rotational Dephasing of Paraterphenyl in a Transient Grating Experiment

David von Seggern, Christian Spitz, Ralf Menzel
2007 Zeitschrift fur physikalische Chemie (Munchen. 1991)  
Transient Grating Spectroscopy / PMMA / Free Volume / Nonpolar Dopant The excited state decay behaviour of p-terphenyl in cyclohexane solution and in a rigid poly(methyl methacrylate) (PMMA) film is reported as measured in a ps polarization dependent transient grating experiment. In both cases, the diffracted intensity shows a biexponential decay. The slower component is attributed to excited state lifetime. In the liquid solution, the faster decay component is described by the hydrodynamical
more » ... he hydrodynamical Stokes-Einstein-Debye theory for rotational reorientation under slip boundary conditions. In the rigid matrix it is interpreted in terms of a free volume effect.
doi:10.1524/zpch.2007.221.4.527 fatcat:r2ant6lcmjbk3j4u7fqkks5374