Synthesis, X-ray Diffraction, and Thermodynamic Properties of Ferrotellurite LuCaFeTeO6

Ferrotellurite with a composition of LuCaFeTeO6 has been synthesized by ceramic technology from oxides Lu2O3 (special purity grade), TeO2 (reagent grade), Fe2O3, and calcium carbonate (analytical grade). The compound was identified X-ray diffractometry. The type of the crystal system, unit cell parameters, and X-ray and pycnometric densities were determined for the compound. The isobaric heat capacity of tellurite was studied by dynamic calorimetry in the temperature range of 298.15–673 K. The equations of the Cp(T) dependence were derived based on these data. The temperature dependences of the thermodynamic functions S°(T), H°(T) – H°(298.15), Фхх(Т), and the heat capacity $$C_{p}^{^\circ }$$ (T) were calculated.