Contributions of Calorimetry for C p Determination and of Scanning Transitiometry for the Study of Polymorphism

Importance of temperature-controlled scanning calorimetry for C p measurements and of scanning transitiometry for simultaneous caloric and pVT analysis in studies of polymorphic systems is demonstrated. Three types of problems of importance in polymorphism of pharmaceutical substances are analyzed: (1) identification of an enantiotropic system with hindered multiphase transitions, with polymorphism in carbamazepine as an example; (2) role of heat capacity determination in understanding homogeneous nucleation, with polymorphism in progesterone as an example; (3) creating a (p,T) unary phase diagram over wide ranges of temperature and pressure, with application to the enantiotropic system of caffeine as an example.