Low Temperature Thermodynamic Properties of La(C₁₀H₁₀F₇O₂)₃

Heat capacity of tris-lanthanum heptafluorodimethyloctanedionate (La(C₁₀H₁₀F₇O₂)₃; CAS no. 19106-89-9) has been measured by the adiabatic method in the range from 10.88 to 300.60 K. Based on the data obtained, the values of thermodynamic functions (entropy, enthalpy increment, and reduced Gibbs energy) have been calculated in the temperature range from 0 to 300 K. As a result of the analysis of the functional behavior of the heat capacity, an anomaly has been revealed in the range of 36–110 K with a maximum at temperature T ≈ 80 K, which indicates the presence of a phase transition in this temperature range. Anomalous contributions to entropy and enthalpy are identified. The possible cause of the detected phase transition has been considered.