CONICET | Buscador de Institutos y Recursos Humanos

There are two contemporary conflicting, indeed, incompatible determinations of measurements of the enthalpies of combustion and of formation of pyrazine-2-carboxylic acid in the literature, (2268.0 ± 0.9 and 271.2 ± 1.1 kJ/mol) and (2211.4 ± 0.9 and 327.8 ± 1.1 kJ/mol). The current paper discusses these two sets of values and from the use of a measurement of the enthalpy of sublimation,a newly evaluated enthalpy of formation of pyrazine itself, and of the quantum chemical calculations at the G3(MP2)//B3LYP level, the former results are accepted and the derived gas phase enthalpy of formation, (167.6 ± 3.1) kJ/mol, suggested.