Heat capacity and thermodynamic functions of new nanostructured cuprate-manganite NdCa2CuMnO6

Abstract

Heat capacities of nanostructured NdCa2CuMnO6 cuprate-manganite are measured by means of dynamic calorimetry on an IT-C-400 unit in the temperature interval of 298.15–673 K. It is established that a λ-shaped phase transition of the second kind is revealed at 348 K on the curve of the dependence C° p ∼ f(T) of NdCa2CuMnO6. Equations for the temperature dependence of the heat capacity of NdCa2CuMnO6 cuprate-manganite are derived from experimental data including the temperature of phase transition. Thermodynamic functions H°(T)-H°(298.15), S°(T), and Φ**(T) are calculated in the interval of 298.15–675 K.