New Possibilities Provided by the Analysis of the Molecular Velocity Autocorrelation Function in Liquids

  • N. P. Malomuzh I.I. Mechnikov National University of Odessa
  • K. S. Shakun Odessa National Maritime Academy
  • A. A. Kuznetsova Odessa National Maritime Academy
Keywords: self-diffusion coefficient, kinematic shear viscosity coefficient, Maxwell relaxation time, argon spinodal, averaged potential of molecular interaction


Long-time tails of the molecular velocity autocorrelation function (VACF) in liquid argon at temperatures higher and lower than the spinodal temperature have been analyzed. By considering the time dependence of the VACF, the self-diffusion and shear viscosity coefficients, and the Maxwell relaxation time are determined, as well as their changes when crossing the spinodal. It is shown that the characteristic changes in the temperature dependences of the indicated kinetic coefficients allow the spinodal position to be determined with a high accuracy. A possibility toapply the proposed method to other low-molecular liquids is considered. As an example, nitrogen and oxygen are used, for which the averaged potential of intermolecular interaction has the Lennard-Jones form.


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How to Cite
Malomuzh, N., Shakun, K., & Kuznetsova, A. (2018). New Possibilities Provided by the Analysis of the Molecular Velocity Autocorrelation Function in Liquids. Ukrainian Journal of Physics, 63(4), 317.
Physics of liquids and liquid systems, biophysics and medical physics