Stability and tensile strength of liquids exhibiting density maxima

If a given liquid exhibits a density maximum anywhere in its phase diagram, thermodynamic consistency dictates that such a point cannot be isolated: a density maxima locus must necessarily exist. For a fluid that does not also exhibit density minima, the pressure‐temperature projection of such a locus is negatively sloped, and can only end at a stability limit. There exist two thermodynamically consistent ways in which such an intersection can occur, and they correspond, respectively, to the highest and lowest possible temperatures at which a liquid can exhibit a negative coefficient of thermal expansion. These theoretical predictions are confirmed by experimental observations. The existence of density anomalies anywhere in a liquid's phase diagram is shown to have a profound influence in determining the shape of such a fluid's stability boundary.