Calculation of Thermodynamic Properties of Germanates Ca3R 2Ge3O12 (R = Y, Er - Lu)

In this work, the standard enthalpy of formation, the standard entropy, and temperature dependence of the heat capacity of compounds with a garnet-like structure Ca3R2Ge3O12 (R = Y, Er - Lu) were determined by various calculation methods. Based on the obtained data, the changes in the Gibbs energy o...

Full description

Saved in:
Bibliographic Details
Published inJournal of Siberian Federal University. Chemistry Vol. 15; no. 3; pp. 409 - 419
Main Authors Chumilina, Lyubov G, Belokopytova, Daria V, Denisov, Viktor M
Format Journal Article
LanguageEnglish
Published Krasnoyarsk Siberian Federal University 01.01.2022
Subjects
Calcium carbonate
Enthalpy
Entropy of formation
Erbium
Garnets
Germanates
Germanium oxides
Lime
Mathematical analysis
Solid phase synthesis
Temperature dependence
Thermodynamic properties
Yttrium
Online AccessGet full text

Cover

More Information
Summary:In this work, the standard enthalpy of formation, the standard entropy, and temperature dependence of the heat capacity of compounds with a garnet-like structure Ca3R2Ge3O12 (R = Y, Er - Lu) were determined by various calculation methods. Based on the obtained data, the changes in the Gibbs energy of synthesis reactions these germanates in the range of 273-1800 K were calculated: a) from initial oxides, b) from calcium carbonate and initial GeO2 and R2O3, c) from initial oxides and pseudobinary compounds. It is shown that the solid-phase synthesis of Ca3R2Ge3O12 garnets is the most thermodynamically advantageous using initial oxides or a mixture of R2O3 and CaGeO3.
ISSN:1998-2836
2313-6049
DOI:10.17516/1998-2836-0304