ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
A new approach is suggested for studying the nature of molecular transport in simple liquids, which makes use of site-specific isotopic substitutions. Its application represents the first systematic experimental study of a theoretically predicted correlation between transport coefficients in liquids and molecular moments of inertia. For this purpose, we have determined the viscosities and self-diffusion coefficients at 25 °C of normal methanol and seven isotopically labeled methanol species: CH3OD, CD3OH, CD3OD, CH2DOH, CHD2OH, CHD2OD, and 13CH3OH. Except for 12C/13C substitution, the observed isotope effects are significantly larger than predicted by a square root of mass dependence, but are well correlated with the square roots of the moments of inertia. The results give strong evidence that translation–rotation coupling influences the transport processes in methanol, thus confirming earlier interpretations of isotope effects upon the transport in water.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.457016
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