Redetermination of low-temperature heat capacity of Cu(C5H7O2)

The heat capacity of copper bis-acetylacetonate (Cu(C5H7O2)(2)) was measured over the temperature range (6.54-313.16) K by adiabatic-shield calorimetry. No anomalies associated with phase transition were found in the functional heat capacity behaviour. The Debye temperature at 0 K was calculated. The data obtained were used to calculate its thermodynamic functions (entropy, enthalpy, reduced Gibbs energy) in the range (0-313) K. They have the following values at 298.15 K: C-p degrees = (283.9 +/- 0.5) J K-1 mol(-1), Delta S-298.15(0)m degrees = (359.1 +/- 0.8) J K-1 mol(-1), Delta H-298.15(0)m degrees = (50.94 +/- 0.09) kJ mol(-1), Phi(m)degrees = (188.3 +/- 1.1) J K-1 mol(-1). The value of the absolute entropy were used to calculate the entropy of formation of Cu(C5H7O2)(2) (cr) at T = 298.15 K. The universal heat capacity behaviour of metal acetylacetonates was demonstrated in a wide temperature range. (C) 2019 Elsevier Ltd.