The Liquid-Solid Transformation in Helium near Absolute Zero

摘要: Although helium is normally a liquid to absolute zero, it can be solidified by the application of moderately high pressures. This transformation particular interest, since third law thermodynamics entropy difference between and solid must disappear as zero approached. most easily shown disappearance heat melting. Measurements from 1.0\ifmmode^\circ\else\textdegree\fi{} 1.8\ifmmode^\circ\else\textdegree\fi{} slope melting pressure curve change in molar volume on are described, which internal energy were calculated. These results verify predictions made law. The measurements also combined with those due earlier workers show discontinuities various thermodynamic functions at intersection $\ensuremath{\lambda}$-point-pressure curve.