A re-examination of herzenbergite–teallite solid solution at temperatures between 300 and 700°C

2001 ◽  
Vol 65 (5) ◽  
pp. 645-651 ◽  
Author(s):  
K. Hayashi ◽  
A. Kitakaze ◽  
A. Sugaki
Keyword(s):  
Solid Solution ◽  
Linear Relationship ◽  
Silica Glass ◽  
Glass Tube ◽  
Solid Solution Series ◽  
Solution Series ◽  
Cell Dimensions ◽  
Silica Glass Tube

AbstractIn order to investigate the range of the solid solution series in herzenbergite-teallite minerals, samples of different composition were synthesized. Herzenbergite-teallite minerals were synthesized by an evacuated silica glass tube method at 700°C. A linear relationship between cell dimensions, a, b and c and composition is established. Extension of solid solution to the Pb-rich portion of the system PbS-SnS is limited; the solid solution area is between Pb1.060Sn0.940S2 and SnS at 700°C. Teallite coexisting with galena was also synthesized by hydrothermal recrystallization at 300, 400 and 450°C. The compositions of teallite are Pb1.140Sn0.860S2 at 300°C, Pb1.114Sn0.886S2 at 400°C, and Pb1.124Sn0.876S2 at 450°C, respectively. Their compositions shift towards the PbS end-member from stoichiometric teallite. The cell dimensions of teallite, which was synthesized hydrothermally, follow the linear relationship between cell dimensions and composition established at 700°C.

Silicon nitride: Enthalpy of formation of the α- and β-polymorphs and the effect of C and O impurities

1999 ◽  
Vol 14 (5) ◽  
pp. 1959-1968 ◽  
Author(s):  
Jian-jie Liang ◽  
Letitia Topor ◽  
Alexandra Navrotsky ◽  
Mamoru Mitomo
Keyword(s):  
Solid Solution ◽  
Enthalpy Of Formation ◽  
Solution Calorimetry ◽  
Molar Enthalpy ◽  
Solid Solution Series ◽  
Solution Series ◽  
Α Phase ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
The Enthalpy Of Formation

High-temperature oxidative drop solution calorimetry was used to measure the enthalpy of formation of α− and β−Si3N4. Two different solvents, molten alkali borate (48 wt% LiBO2 · 52 wt% NaBO2) at 1043 and 1073 K and potassium vanadate (K2O · 3V2O5) at 973 K, were used, giving the same results. Pure α− and β−Si3N4 polymorphs have the same molar enthalpy of formation at 298 K of −850.9 ± 22.4 and −852.0 ± 8.7 kJ/mol, respectively. The unit cell dimensions of impure α−Si3N4 samples depend linearly on the O and C impurity contents, and so does the molar enthalpy of formation. The energetic stability of the α−Si3N4phase decreases when the sample contains O and C impurities. The experimental evidence strongly suggests that the impurities dissolve into the α−Si3N4 structure to form a (limited) isostructural solid solution series but that this solid solution series is energetically less stable than a mechanical mixture of pure (α or β) Si3N4, SiO2, and SiC. Thus, the α-phase is not stabilized by impurities and is probably always metastable.

The crystal structure of ammoniojarosite, (NH4)Fe3(SO4)W(OH)6 and the crystal chemistry of the ammoniojarosite–hydronium jarosite solid-solution series

2007 ◽  
Vol 71 (4) ◽  
pp. 427-441 ◽  
Author(s):  
L. C. Basciano ◽  
R. C. Peterson
Keyword(s):  
Solid Solution ◽  
Short Wave ◽  
Unit Cell ◽  
Solid Solution Series ◽  
Hydrogen Atoms ◽  
Solution Series ◽  
Hydronium Jarosite ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
End Members

AbstractThe atomic structure of ammoniojarosite,[(NH4)Fe3(SO4)2(OH)6], a = 7.3177(3) Å, c = 17.534(1) Å, space group Rm, Z = 3, has been solved using single-crystal X-ray diffraction (XRD) to wR 3.64% and R 1.4%. The atomic coordinates of the hydrogen atoms of the NH4 group were located and it was found that the ammonium group has two different orientations with equal probability. Hydronium commonly substitutes into jarosite group mineral structures and samples in the ammoniojarosite–hydronium jarosite solid-solution series were synthesized and analysed using powder XRD and Rietveld refinement. Changes in unit-cell dimensions and bond lengths are noted across the solidsolution series. The end-member ammoniojarosite synthesized in this study has no hydronium substitution in the A site and the unit-cell dimensions determined have a smaller a dimension and larger c dimension than previous studies. Two natural ammoniojarosite samples were analysed and shown to have similar unit-cell dimensions to the synthetic samples. Short-wave infrared and Fourier transform infrared spectra were collected for samples from the NH4–H3O jarosite solid-solution series and the differences between the end-members were significant. Both are useful tools for determining NH4 content in jarosite group minerals.

Some topaz-, sillimanite-, and kyanite-bearing rocks from Tanzania

1967 ◽  
Vol 36 (280) ◽  
pp. 515-521 ◽  
Author(s):  
D. R. C. Kempe
Keyword(s):  
Solid Solution ◽  
Optical Properties ◽  
Solid Solution Series ◽  
Solution Series ◽  
Physico Chemical ◽  
Cell Dimensions ◽  
Chemical Conditions ◽  
Abnormal Results

SummarySome sillimanite-kyanite quartzites, which may grade into sillimanite-kyanite topazfels, from NE. Tanzania are described. In view of the suggestion that a solid-solution series might exist between topaz and sillimanite, the cell dimensions and some optical properties of both minerals were investigated. No abnormal results, suggesting solid solution, were obtained and the coexistence of topaz, sillimanite, and kyanite is ascribed to particular physico-chemical conditions.

The Crystal Structure of Bi2PbMnO4(PO4)2, a Member of a New Solid Solution Series in the Bi–Pb–Mn–P Oxide System

2002 ◽  
Vol 165 (2) ◽  
pp. 324-333 ◽  
Author(s):  
Olivier Cousin ◽  
Marielle Huve ◽  
Pascal Roussel ◽  
Olivier Perez ◽  
Hugo Steinfink
Keyword(s):  
Crystal Structure ◽  
Solid Solution ◽  
Oxide System ◽  
Solid Solution Series ◽  
Solution Series

Rietveld refinement of the solid-solution series: (Cu,Mg)SO4·H2O

1995 ◽  
Vol 10 (3) ◽  
pp. 189-194 ◽  
Author(s):  
C. L. Lengauer ◽  
G. Giester
Keyword(s):  
Solid Solution ◽  
Rietveld Refinement ◽  
Powder Diffraction ◽  
Rietveld Method ◽  
Structure Refinement ◽  
Solid Solution Series ◽  
Cation Site ◽  
Tg Analysis ◽  
X Ray ◽  
Solution Series

The kieserite-type solid-solution series of synthetic (Cu,Mg)SO4·H2O was investigated by TG-analysis and X-ray powder diffraction using the Rietveld method. Representatives with Cu≥20 mol% are triclinic distorted () analogous to the poitevinite (Cu,Fe)SO4·H2O compounds. Cation site ordering with preference of Cu for the more distorted M1 site was additionally proven by the structure refinement.

ChemInform Abstract: The Solid Solution Series (GeTe)x(LiSbTe2)2(1 ≤ x ≤ 11) and the Thermoelectric Properties of (GeTe)11(LiSbTe2)2.

ChemInform ◽  
2013 ◽  
Vol 44 (50) ◽  
pp. no-no
Author(s):  
Thorsten Schroeder ◽  
Stefan Schwarzmueller ◽  
Christian Stiewe ◽  
Johannes de Boor ◽  
Markus Hoelzel ◽  
...  
Keyword(s):  
Solid Solution ◽  
Thermoelectric Properties ◽  
Solid Solution Series ◽  
Solution Series
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