Abstract:
Phase transitions are very commonly observed in nature and related topics
are of much research interest [1–26]. The change of phase in a system takes
place due to variation in different thermodynamic variables, like pressure (P ),
temperature (T ), magnetic field (h), etc. In addition to being fundamental
to the understanding of matter, knowledge of it is important in technological
developments. In Fig. 1.1 we show a schematic phase diagram [1] of a normal
chemical substance in the P − T plane. The three distinct phases, viz., solid,
liquid and gas, in this figure, are separated by different coexistence curves,
along each of which two phases coexist with each other in equilibrium. For
example, along the red curve, referred to as the fusion curve [1], solid and
liquid phases coexist. The gas-solid (pink curve) and gas-liquid (green curve)
coexistence curves are referred to as the sublimation and the vaporization
curves, respectively [1].
