Temperature dependence of solute vibrational relaxation in supercritical fluids: experiment and theory
نویسندگان
چکیده
Ž . Ž . Vibrational lifetime T data for the asymmetric CO stretching mode of W CO in supercritical ethane and carbon 1 6 w x dioxide as a function of temperature at various fixed densities are compared to a recent extended hydrodynamic theory 1 . In ethane at the critical density, as the temperature is raised, T initially becomes longer, reaching a maximum ;70 K above 1 the critical temperature. T decreases with further increase in temperature. The theory is able to reproduce this behavior 1 nearly quantitatively without free parameters. At high density in ethane and in CO , the inverted temperature dependence is 2 not observed, in agreement with theoretical calculations. q 2000 Published by Elsevier Science B.V.
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