1, Competence Center °CALOR, Rostock University, Rostock, MV, Germany
3, Institute of Chemistry, Rostock University, Rostock, MV, Germany
4, Kazan Federal University, Kazan, , Russian Federation
The determination of the thermophysical properties, e.g. fusion temperature, fusion enthalpy, sublimation enthalpy and vapour pressure lay within focus of many scientific fields and industrial applications. These values are directly connected to the intermolecular forces in crystal state, provides the lattice energy, change in ordering by going from crystal to gas phase and the solubility properties of organic molecules.
In many cases investigation of thermally labile systems e.g. biomolecules at slow heating rates are accomplished with low thermal stability of them. The application of classic techniques to measure their thermophysical properties often fails, making the estimation of the corresponding thermodynamic parameters, like melting temperature, enthalpy of fusion, vapor pressure highly inaccurate or even impossible.
In the present study, fast scanning calorimetry was successfully applied for determination of the sublimation vapour pressure, enthalpies of sublimation and melting behaviour of the nucleobases cytosine, thymine, adenine, uracil and guanine, the building blocks of DNA and RNA, which are known to decompose at high temperature.