Высокотемпературная теплоемкость TmBiGeO-=SUB=-5-=/SUB=- и YbBiGeO-=SUB=-5-=/SUB=-

Abstract

The TmBiGeO_5 and YbBiGeO_5 compounds have been synthesized from Tm_2O_3 (Yb_2O_3), Bi_2O_3, and GeO_2 oxides by the solid-state synthesis with successive burning at 1003, 1073, 1123, 1143, 1173, and 1223 K. High-temperature specific heat of the oxide compounds has been measured by differential scanning calorimetry. Basing on the experimental dependences C _p = f ( T ), the thermodynamic properties of the oxide compounds, i.e., the enthalpy and entropy variations, have been calculated.