A semiempirical method for calculating the surface density of Gibbs energy at the crystal-liquid interface

Surface tension sigma at the crystal-melt interface at atmospheric pressure was calculated from the experimental data on the kinetics of spontaneous crystallization of the supercooled liquid with the use of homogeneous nucleation theory. The region of sigma definition along the melting curve p(SL) = f(T) was extended to its metastable continuation behind the triple point based on thermodynamic similarity considerations. The constancy of the Nc dimensionless complex relating sigma to entropy jumps caused by melting and to the specific crystal volume was postulated for a large portion of the melting curve. The p(SL)(T) function was approximated by the Simon equation. In this approximation, the sigma (T) temperature dependences were constructed for Ar, Na, Sn, Hg, and Pb. The sigma (T) functions were shown to be characterized by the presence of maxima.