X-ray diffraction and thermodynamic characteristics for tellurite of the composition Li2CeTeO5

Resumo

Tellurite of the composition Li₂CeTeO₅ is synthesized by solid-phase method from cerium(IV) and tellurium(IV) oxides and lithium carbonate. The type of syngony, the unit cell parameters, and the compound’s X-ray and pycnometry densities are determined via X-ray diffraction analysis. The isobaric heat capacity of lithium–cerium tellurite is studied by means of dynamic calorimetry in the temperature range of 298.15–673 K; the results serve as the basis for deriving C_p^° ~ f(T) dependency equations and determining the compound’s thermodynamic functions. λ-shaped anomalous effects, due probably to Type II phase transitions, are found on the C_p^° ~ f(T) dependence.