Thermodynamic relations among olivine, spinel, and phenacite structures in silicates and germanates. III. The system CuO‒MgO‒GeO2

A. Navrotsky

doi:10.1016/0022-4596(74)90140-6

Thermodynamic relations among olivine, spinel, and phenacite structures in silicates and germanates. III. The system CuO‒MgO‒GeO2

A. Navrotsky

Molecular Sciences, School of (SMS)

Research output: Contribution to journal › Article › peer-review

20 Scopus citations

Abstract

Phase relations in the system CuO{single bond}MgO{single bond}GeO₂ in air at 1000°C were determined. Activity-composition relations in the system CuO{single bond}MgO at 1000°C were measured: the guggenite phase was found to exist over the composition range 0.695 < X_CuO < 0.805. The enthalpy and free energy of formation of CuGeO₃ were determined by high temperature solution calorimetry and reduction equilibria, respectively. For the reaction: CuO + GeO₂ = CuGeO₃,ΔG°₁₂₇₃ = -4.0kcal/mole, ΔH°₉₈₈ = -5.2kcal/mole, ΔS° = -0.9cal/deg mole. The stability of rocksalt, tenorite, olivine, enstatite, and CuGeO₂ structures in this system is discussed.

Original language	English (US)
Pages (from-to)	10-16
Number of pages	7
Journal	Journal of Solid State Chemistry
Volume	11
Issue number	1
DOIs	https://doi.org/10.1016/0022-4596(74)90140-6
State	Published - Sep 1974

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials
Ceramics and Composites
Condensed Matter Physics
Physical and Theoretical Chemistry
Inorganic Chemistry
Materials Chemistry

Access to Document

10.1016/0022-4596(74)90140-6

Cite this

@article{25ef5e5ef1964a7a882c480f4759c55b,

title = "Thermodynamic relations among olivine, spinel, and phenacite structures in silicates and germanates. III. The system CuO‒MgO‒GeO2",

abstract = "Phase relations in the system CuO{single bond}MgO{single bond}GeO2 in air at 1000°C were determined. Activity-composition relations in the system CuO{single bond}MgO at 1000°C were measured: the guggenite phase was found to exist over the composition range 0.695 < XCuO < 0.805. The enthalpy and free energy of formation of CuGeO3 were determined by high temperature solution calorimetry and reduction equilibria, respectively. For the reaction: CuO + GeO2 = CuGeO3,ΔG°1273 = -4.0kcal/mole, ΔH°988 = -5.2kcal/mole, ΔS° = -0.9cal/deg mole. The stability of rocksalt, tenorite, olivine, enstatite, and CuGeO2 structures in this system is discussed.",

author = "A. Navrotsky",

note = "Funding Information: This work was supported by the National Science Foundation (Grant GP20402 and GH39767). The GeO2 used was donated by the Sylvania Corporation. D. S. Kenny, L. Ryan, and J. Sharples participated in various aspects of the experimental work.",

year = "1974",

month = sep,

doi = "10.1016/0022-4596(74)90140-6",

language = "English (US)",

volume = "11",

pages = "10--16",

journal = "Journal of Solid State Chemistry",

issn = "0022-4596",

publisher = "Academic Press Inc.",

number = "1",

}

TY - JOUR

T1 - Thermodynamic relations among olivine, spinel, and phenacite structures in silicates and germanates. III. The system CuO‒MgO‒GeO2

AU - Navrotsky, A.

N1 - Funding Information: This work was supported by the National Science Foundation (Grant GP20402 and GH39767). The GeO2 used was donated by the Sylvania Corporation. D. S. Kenny, L. Ryan, and J. Sharples participated in various aspects of the experimental work.

PY - 1974/9

Y1 - 1974/9

N2 - Phase relations in the system CuO{single bond}MgO{single bond}GeO2 in air at 1000°C were determined. Activity-composition relations in the system CuO{single bond}MgO at 1000°C were measured: the guggenite phase was found to exist over the composition range 0.695 < XCuO < 0.805. The enthalpy and free energy of formation of CuGeO3 were determined by high temperature solution calorimetry and reduction equilibria, respectively. For the reaction: CuO + GeO2 = CuGeO3,ΔG°1273 = -4.0kcal/mole, ΔH°988 = -5.2kcal/mole, ΔS° = -0.9cal/deg mole. The stability of rocksalt, tenorite, olivine, enstatite, and CuGeO2 structures in this system is discussed.

AB - Phase relations in the system CuO{single bond}MgO{single bond}GeO2 in air at 1000°C were determined. Activity-composition relations in the system CuO{single bond}MgO at 1000°C were measured: the guggenite phase was found to exist over the composition range 0.695 < XCuO < 0.805. The enthalpy and free energy of formation of CuGeO3 were determined by high temperature solution calorimetry and reduction equilibria, respectively. For the reaction: CuO + GeO2 = CuGeO3,ΔG°1273 = -4.0kcal/mole, ΔH°988 = -5.2kcal/mole, ΔS° = -0.9cal/deg mole. The stability of rocksalt, tenorite, olivine, enstatite, and CuGeO2 structures in this system is discussed.

UR - http://www.scopus.com/inward/record.url?scp=0346966229&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0346966229&partnerID=8YFLogxK

U2 - 10.1016/0022-4596(74)90140-6

DO - 10.1016/0022-4596(74)90140-6

M3 - Article

AN - SCOPUS:0346966229

SN - 0022-4596

VL - 11

SP - 10

EP - 16

JO - Journal of Solid State Chemistry

JF - Journal of Solid State Chemistry

IS - 1

ER -

Thermodynamic relations among olivine, spinel, and phenacite structures in silicates and germanates. III. The system CuO‒MgO‒GeO2

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this