A first-order phase transition in mercury vapour

Abstract

The results of sound velocity measurements in mercury, performed at temperatures from 300 up to 2050 K and pressures from 30 up to 1900 bar by a precise pulsed phase-sensitive technique for frequency 10 MHz, are presented. The data obtained contain direct evidence of a first-order plasma phase transition in mercury that takes place in the vapour near saturation and in the supercritical fluid.