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Critical exponent for viscosity



Robert F. Berg, Michael R. Moldover


We have measured the critical exponent y characterizing the divergence of the viscosity eta  |T – Tc|^-y for carbon dioxide and xenon. The values of y for both fluids fall within the range y = 0.041 ± 0.001 and are consistent with the range y = 0.042 ± 0.002 spanned by our earlier data for four binary liquid mixtures. This agreement is the strongest evidence that pure fluids and binary liquids are in the same dynamic universality class; however, the results for y are inconsistent with the recent theoretical value of 0.032.
Physical Review A
Created December 15, 1990, Updated February 17, 2017