Relaxation configurational heat capacity

The second term on the right is called the configurational heat capacity, and is due to the relaxation of system to the equilibrium configuration (Kondepudi and Prigogine, 1999)... 

Angell [43] takes the configurational heat capacity as inversely proportional to absolute temperature, ACp = KIT, where A " is a constant of the material. With this relationship, the relaxation time in Eq. (3) becomes... 

The term hT,p d /dT) is called the configurational heat capacity, as it refers to the heat capacity due to the relaxation of the system to the equilibrium configuration. The configurational heat capacity can be observed in systems such as glycerin when it is a supercooled liquid. The molecules can vibrate but not rotate freely as they do in the liquid state. This restricted motion is called libration. As the temperature is increased, a greater fraction of the molecules begin to rotate. For this system the variable is the extent of reaction for the libration-rotation transformation. For glycerin there exists a state called the... 

---