A Variational Technique for Thermodynamics of Liquid K(1-x)Rbx Alloys

Keywords: thermodynamical properties, liquid alkali alloy, pseudopotential theory, variational approach, Gibbs-Bogoliubov inequality


Liquid K_(1-x) Rb_x binary alloys with various thermodynamical proportions of participating elements are investigated. The properties of thermodynamic interest are included in the study. The internal energy (Fint), Helmholtz free enrgy (FHand the entropy (S) have been calculated in a concentration range from X=0.0 to X=1.0 increasing in a step of 0.1 in the present work. Apart from the internal energy (Fint), various contributions to this energy are also calculated and separately depicted in the present article. A variational approach has been adopted for the present calculation. A single potential with a set of two parameters is used for the calculation of all properties of the alloys. Static Hartree local field function (H) is used to consider screening effect. Various local field correction functions are used to take into account the exchange and correlation effect. Comparison with experimental data at some concentration shows the good agreement with the presently obtained data. With the help of current results, the applied model potential found very suitable with individual parameters for thermodynamical study. As the present results provide the data even where minimum availability of the experimental findings, it can serve as a data base for the future calculation which deals with thermodynamics of the liquid alloys. Present results allow one to get proportion based tuned properties of the K_(1-x) Rb_x for different requirements.


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Malan, R., & Vora, A. (2021). A Variational Technique for Thermodynamics of Liquid K(1-x)Rbx Alloys. East European Journal of Physics, (2), 122-126. https://doi.org/10.26565/2312-4334-2021-2-09