Effect of Atomic Size on the Isothermal Bulk Modulus and Surface Tension of Liquid Metals

Abstract

The isothermal bulk modulus $K_{{T_{m}}}$ and surface tension γ_m of liquid metals at the melting point increase with decreasing atomic size a, and these dependences are similar to one another. It is shown that transition metals with a hexagonal closed-packed and body-centered cubic structure are concentrated above the γ_m−$K_{{T_{m}}}$ regression line, and face-centered cubic metals are below this line. In alkali, alkaline earth, rare earth metals, the surface tension γ_m with a change in the isothermal bulk modulus $K_{{T_{m}}}$ increases several times more intensively than in transition metals. The reduced quantities of isothermal bulk modulus and surface tension have been introduced. The reduced surface tension demonstrates high coincidence with atomic size parameter a⁻², and the reduced isothermal bulk modulus with atomic size parameter a⁻³. The ratio of the surface tension to the product of the atomic size and the isothermal bulk modulus γ_m×(a $K_{{T_{m}}}$)⁻¹ compares the energy of atoms on the surface and in the bulk.