Recent work in our group has established a well characterised equation of state (EoS) for sodium fluoride. Our work here accurately defines an EoS across both pressure and temperature, and incorporates data from multiple experimental methods. This EoS has the capacity to be used as a pressure calibrant in circumstances where other options are not suitable, and offers several unique advantages. In addition, it is remarkably capable of reproducing thermodynamic data simply from PVT measurements. One example where this has thus far been useful is in the high-pressure investigations into the structure of XeF2. In this talk I will discuss the intricacies of fitting this data, and the predictive power that EoS of this type can give.