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Inorganic Materials

, Volume 54, Issue 12, pp 1245–1249 | Cite as

Heat Capacity of In2Ge2O7 and YInGe2O7 from 320 to 1000 K

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

Abstract

Polycrystalline In2Ge2O7 and YInGe2O7 samples have been prepared by solid-state reactions, by sequentially firing stoichiometric mixtures of In2O3, Y2O3, and GeO2 at temperatures from 1273 to 1473 K. The molar heat capacity of the indium and yttrium indium pyrogermanates has been determined by differential scanning calorimetry in the range 320–1000 K. The experimental Cp(T) data have been used to evaluate the enthalpy increment, entropy change, and reduced Gibbs energy of In2Ge2O7 and YInGe2O7.

Keywords:

indium germanate yttrium indium germanate high-temperature heat capacity thermodynamic properties 

Notes

ACKNOWLEDGMENTS

This work was supported by the Russian Federation Ministry of Education and Science (state research target for Siberian Federal University in 2017–2019, project no. 4.8083.2017/8.9: Establishing a Database of Thermodynamic Characteristics of Multifunctional Mixed-Oxide Materials Containing Rare and Trace Elements; state research target no. 007-00129-18-00).

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Copyright information

© Pleiades Publishing, Inc. 2018

Authors and Affiliations

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

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