First-Order Phase Transition in the Framework of the Cell Fluid Model: Regions of Chemical Potential Variation and the Corresponding Densities


  • I.V. Pylyuk Institute for Condensed Matter Physics, Nat. Acad. of Sci. of Ukraine
  • M.P. Kozlovskii Institute for Condensed Matter Physics, Nat. Acad. of Sci. of Ukraine



cell fluid model, chemical potential, density, equation of state, binodal


A microscopic description is given for the behavior of the fluid system in an immediate vicinity of its critical point, where theoretical and experimental researches are difficult to carry out. For the temperatures T < TC, the regions of chemical potential and density variations are singled out and analyzed. The equation of state of the cell fluid model in terms of temperature-chemical potential is written using the Heaviside functions. This equation is also given in terms of the temperature and density variables. As a result of the study of the relationship between the density and the chemical potential, an equation for the binodal curve is obtained in a narrow neighborhood of the critical point.


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How to Cite

Pylyuk, I., & Kozlovskii, M. (2022). First-Order Phase Transition in the Framework of the Cell Fluid Model: Regions of Chemical Potential Variation and the Corresponding Densities. Ukrainian Journal of Physics, 67(1), 54.



Physics of liquids and liquid systems, biophysics and medical physics