Mechanical and dielectric relaxation spectra in seven highly viscous glass formers

Physics – Condensed Matter – Disordered Systems and Neural Networks

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Contribution to the Ngai Fest issue of J. Non-Cryst. Solids; 8 pages, 8 figures, 30 references

Scientific paper

10.1016/j.jnoncrysol.2007.04.034

Published dielectric and shear data of six molecular glass formers and one polymer are evaluated in terms of a spectrum of thermally activated processes, with the same barrier density for the retardation spectrum of shear and dielectrics. The viscosity, an independent parameter of the fit, seems to be related to the high-barrier cutoff time of the dielectric signal, in accordance with the idea of a renewal of the relaxing entities after this critical time. In the five cases where one can fit accurately, the temperature dependence of the high-barrier cutoff follows the shoving model. The Johari-Goldstein peaks, seen in four of our seven cases, are describable in terms of gaussians in the barrier density, superimposed on the high-frequency tail of the $\alpha$-process. Dielectric and shear measurements of the same substance find the same peak positions and widths of these gaussians, but in general a different weight.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Mechanical and dielectric relaxation spectra in seven highly viscous glass formers does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Mechanical and dielectric relaxation spectra in seven highly viscous glass formers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mechanical and dielectric relaxation spectra in seven highly viscous glass formers will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-672877

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.