Low-temperature heat capacity of dysprosium diboride

Heat capacity Cp(T) of dysprosium diboride is experimentally investigated at the temperatures of 5–300 K. On the dependence Cp(T) smooth anomaly at the temperatures of 15–20 K and sharp anomalies at Tm1=47.8 K and Tm2=178.8 K are revealed. Anomaly at Tm1 is caused, obviously, by ferromagnetic phase transition in DyB2. The lattice contribution to DyB2 heat capacity is determined by comparison with heat capacity of non-magnetic YB2. The estimation of Schottky contribution to DyB2 heat capacity is made, the scheme of splitting of the ground state of Dy3+ ion is offered.