Heat Capacity Function, Enthalpy of Formation and Absolute Entropy of Mg(AlH4 )2

Abstract

In this investigation, we set out first to characterize the thermodynamics of Mg(AlH₄ )₂ and secondly to use the determined data to reevaluate and update existing estimation procedures for heat capacity functions, enthalpies of formation and absolute entropies of alanates. Within this study, we report the heat capacity function of Mg(AlH₄ )₂ in the temperature range from 2 K to 370 K and its enthalpy of formation and absolute entropy at 298.15 K, being $-70.6\pm 3.6$ kJ mol^-1 and 133.06 J (K mol)^-1 , respectively. Using these values, we updated and expanded methods for the estimation of thermodynamic data of alanates.

Keywords: Calorimetry; Entropy; Heat Capacity; Heats of Formation; Hydrides.