ABSTRACT
The sign of Δ C p https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781351077286/2f51899c-87f0-465d-b4f5-93b9b017b3cc/content/eq133.tif"/> at the glass transition is defined uniquely. It does not depend on the vitreous state resulting from either nonequilibrium cooling or step “superheating” of the initial equilibrium liquid of high viscosity. A similar conclusion applies to the increase in compressibility. There is no such situation at phase transitions of the first order. In such cases the succession of changing phases is defined solely by the line of equal thermodynamic potentials (Figure 1).
