What can we learn by squeezing a liquid?
Relaxation times tau(T,upsilon) for different temperatures, T, and specific volumes, upsilon, collapse to a master curve vs Tupsilon(gamma), with gamma a material constant. The isochoric fragility, mV, is also a material constant, inversely correlated with gamma. From these experimental facts, we obtain a three-parameter function that accurately fits tau(T,upsilon) data for several glass-formers over the supercooled regime, without any divergence of tau below Tg. Although the values of the three parameters depend on the material, only gamma significantly varies; thus, by normalizing material-specific quantities related to gamma, a universal power law for the dynamics is obtained.
Casalini
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Naval Research Laboratory, Code 6120, Washington, D.C. 20375-5342, George Mason University, Fairfax Virginia 22030, USA. casalini@ccs.nrl.navy.mil
Capaccioli
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Roland
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