DYNAMICS OF THE POLYMER MATRIX IN PPO-CENTER-DOT-NACLO4 AND PPO-CENTER-DOT-LICLO4 COMPLEXES STUDIED BY QENS

Quasi-elastic neutron scattering spectra have been measured for PPO . LiClO4 and PPO . NaClO4 complexes with two spectrometer resolutions (5 and 15 mu eV) at three temperatures: 305, 325, and 345 K. The spectra have been analysed by two approaches: (i) Bayesian analysis of Lorent zian components, and (ii) an assumption of a stretched exponential int ermediate scattering function. Both analyses agree well with the data in a mathematical sense but the results are unsatisfactory in a physic al sense. The indications are that the true line shapes are more compl ex, and involve at least two components corresponding to faster and sl ower relaxations.