Thermal analysis enthalpy contribution

DSC analysis represents a superior method of thermal analysis, in that the area under a DSC peak is directly proportional to the heat absorbed or evolved by the thermal event, and integration of these peak areas yields the enthalpy of reaction (in units of calor-ies/gram or Joules/gram). Even though conclusions reached on the basis of enthalpies of fusion are possibly compromised by their omission of the entropy contribution, an indication of the thermodynamic trends inherent in the system is often possible. For instance, the same polymorphic form of moricizine hydrochloride was deduced on the basis of thermal analysis and equilibrium solubility measurements. On the other hand, auranofin represents a compound for which one anhydrous polymorphic form is predicted to be the most stable by virtue of its melting point and heat of fusion but for which solubility measurements demonstrate that the other polymorph was in fact the thermodynamically stable form. ... 

The thermochemistry and thermal effects of reactions involving dithio-phosphoric acids have been analyzed and the formation enthalpies of a series of dithiophosphates determined. Analysis of the resulting experimental data was carried out on the basis of an additive scheme. Group contributions into the vaporization and formation enthalpies were determined and thermochemical characteristics of the compounds were calculated. 

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