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Oxides Y0.65Pr0.35BiGeO5 and Y0.65Nd0.35BiGeO5 have been synthesized by a ceramic method. The heat capacity of fine crystalline samples has been studied in the range 350-1000 K by differential scanning calorimetry. The Cp = f(T) dependences can be described by the Maier-Kelley equation. The thermodynamic functions of these oxides—changes in enthalpy, entropy, and reduced Gibbs energy—have been calculated from the experimental data on high-temperature heat capacity. [ABSTRACT FROM AUTHOR]

The heat capacities of PbVO and Pb(VO) as a function of temperature in the range 350-965 K have been studied by the differential scanning calorimetry method. The C = f( T) curve for PbVO is described by the equation C = (230.76 ± 0.51) + (73.60 ± 0.50)×10 T − (18.38 ± 0.54)×10 T in the entire temperature range. For Pb(VO), there is a well-pronounced extreme point in the C = f( T) curve at T = 371.5 K, which is caused by the existence of a structural phase transition. The thermodynamic properties of the oxide compounds have been calculated. [ABSTRACT FROM AUTHOR]