Heat capacity and thermodynamic properties of alkali and alkali-earth borohydrides

In this work, the above room temperature heat capacity for different polymorphs of alkali and alkali-earth (i.e. Na, K, Rb, Cs, Mg, Ca) borohydrides has been measured by DSC as a function of temperature. The above room temperature measured C-p values have been compared with available extrapolated literature data, and they have been modelled as a function of temperature according to the Calphad method. The variations of C-p values for different polymorphs were studied in details and they have been related to the corresponding crystal structures, considering the mobility of the BH4 group. From the whole set of assessed thermodynamic data, possible correlations with dynamics and structural properties have been estimated. (C) 2020 Elsevier Ltd.