Low-temperature thermodynamic properties of holmium selenide (2:3)

Abstract Holmium selenide Ho 2 Se 3 (cr) was synthesized and characterized by powder X-ray diffraction and energy dispersive analysis. The heat capacity of Ho 2 Se 3 (cr) has been measured by adiabatic method in the temperature range of (4.75–302.60) K. The pronounced λ-anomalies were found in C p,m ( T ) dependence with the maxima at temperatures T C1  = 6.03 K and T C2  = 228.40 K. A conclusion was drawn that the phase transition associated with antiferromagnetic ordering is observed at T C1 . The values of thermodynamic function (entropy, enthalpy and Gibbs reduced energy) were calculated from the experimental C p ( T ) dependence. Absolute entropy value was used for calculation of Ho 2 Se 3 (cr) formation entropy at T  = 298.15 K.