Slow mode cluster interpretation

The NaPSS/LaCl3 dynamics is characterized by a bimodal decay of the concentration correlation function at very low salt concentration. Two dynamic modes (fast and slow) are present. The fast process is interpreted as a diffusion of blobs of a transient network in the semidilute regime. The origin of the slow mode is not always understood. It can be interpreted as the diffusion of multichain domains (clusters). Due to the large dimensions of the domains, the slow mode does not correspond to a pure diffusive motion. 

The slow mode s properties correspond to the predicted properties of a Kivelson glass, in which the glass transition is driven by the formation of local clusters that cannot for some reason grow into space-filling lattices. By this interpretation, as supported by the near-equality of the longest relaxation times of the slow mode and the viscoelastic moduli, at least some polymer viscoelastic properties would seem to be driven by the interaction of a dispersion of vitrified regions within polymer solutions. 

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