Thermodynamic properties and phonon density of states of Tb2(C11H19O2)6

Abstract

The high-temperature thermodynamic properties of the terbium tris-dipivaloylmethanate dimer [Tb(C11H19O2)3]2 are studied. Heat capacity was measured by DSC in the range of 300–474 K. No anomalies in the heat capacity associated with phase transitions below the melting point were found. The isobaric thermodynamic functions: entropy, enthalpy increment and Gibbs energy in the range of 300–435 K were calculated. Based on the low-temperature heat capacity, the phonon density of states of terbium dipivaloylmethanate was calculated. Main characteristic temperatures, zero-point energy, isochoric heat capacity and thermodynamic functions: entropy, internal energy increment and Helmholtz energy in the entire region of the solid phase existence were obtained. Accuracy of the obtained results was estimated and the results were compared with the known data.