Liquid–liquid transition in elemental liquids investigated by sound velocity measurements: trends in the periodic table

Abstract

Abstract The velocity of sound has been measured as a function of temperature to investigate structural changes in the molten As–Sb alloy. The overall profile of temperature dependence of the sound velocity changes smoothly from Sb to As. The results indicate that a tendency to change structures in the supercooled state develops with increasing As fraction, and confirm the previous conclusion that molten As changes rapidly its structure in the undercooled state and is already in the high-temperature side of an assumed liquid – liquid transition at the melting point. By confirming the structural transition in molten As, it is possible to mark the elements in the periodic table that undergo a crossover liquid –liquid transition around the melting point under the saturating vapor pressure. Observed trends for liquid – liquid transitions are discussed on the basis of the Peierls distortion mechanism.