Inorganic Materials

, Volume 54, Issue 4, pp 361–365 | Cite as

Synthesis and High-Temperature Heat Capacity of Dy2Ge2O7 and Ho2Ge2O7

  • L. T. Denisova
  • L. A. Irtyugo
  • Yu. F. Kargin
  • N. V. Belousova
  • V. V. Beletskii
  • V. M. Denisov


The Dy2Ge2O7 and Ho2Ge2O7 pyrogermanates have been prepared by solid-state reactions in several sequential firing steps in the temperature range 1237–1473 K using stoichiometric mixtures of Dy2O3 (or Ho2O3) and GeO2. The heat capacity of the synthesized germanates has been determined as a function of temperature by differential scanning calorimetry in the range 350–1000 K. The experimentally determined C p (T) curves of the dysprosium and holmium germanates have no anomalies and are well represented by the Maier–Kelley equation. The experimental C p (T) data have been used to evaluate the thermodynamic functions of the Dy2Ge2O7 and Ho2Ge2O7 pyrogermanates: enthalpy increment H°(T)–H°(350 K), entropy change S°(T)–S°(350 K), and reduced Gibbs energy Ф°(T).


solid-state synthesis dysprosium and holmium germanates differential scanning calorimetry heat capacity thermodynamic properties 


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Copyright information

© Pleiades Publishing, Ltd. 2018

Authors and Affiliations

  • L. T. Denisova
    • 1
  • L. A. Irtyugo
    • 1
  • Yu. F. Kargin
    • 2
  • N. V. Belousova
    • 1
  • V. V. Beletskii
    • 1
  • V. M. Denisov
    • 1
  1. 1.Institute of Nonferrous Metals and Materials ScienceSiberian Federal UniversityKrasnoyarskRussia
  2. 2.Baikov Institute of Metallurgy and Materials ScienceRussian Academy of SciencesMoscowRussia

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