32
Views
2
CrossRef citations to date
0
Altmetric
Original Articles

Effect of the isobaric and isothermal reductions in excess and configurational entropies on glass-forming dynamics

, , , &
Pages 1513-1519 | Published online: 02 Sep 2006
 

Abstract

Dielectric relaxation times τ, over a broad range of temperatures and pressures for simple molecular glass-forming systems reveal good agreement with the pressure-extended Adam–Gibbs equation derived from the Adam–Gibbs model, relating directly the dynamics to the thermodynamics through the configurational entropy S c, assuming it to be proportional to the excess entropy S exc of the melt with respect to the crystal. In the present study by making use of both calorimetric and expansivity measurements it was possible to make an accurate determination of the pressure and temperature dependences of S exc over the whole investigated range, and the expected proportionality between S c and S exc was experimentally checked. Results show that different proportionality factors g P and g T exist between S c and S exc in isothermal and isobaric conditions and the ratio g T/g P of these is nearly 0.7 for all the systems.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.