scholarly journals Resonance of mixing energy and energy of elastic deformations during spinodal decomposition and the composition modulation effect in ZnхCd1-ХTe solid solutions

10.30544/614 ◽  
2021 ◽  
Vol 27 (3) ◽  
pp. 385-396
Author(s):  
Pavel Moskvin ◽  
Sergii Skurativskyi ◽  
Wojciech Sadowski ◽  
Barbara Koscielska ◽  
Petro Melnychuk ◽  
...  
Keyword(s):  
Solid Solution ◽  
Spinodal Decomposition ◽  
Solid Solutions ◽  
State Diagram ◽  
Resonance Phenomenon ◽  
Modulation Effect ◽  
Composition Modulation ◽  
Mixing Energy ◽  
Close Proximity ◽  
Cahn Hilliard Equation

The Cahn-Hilliard equation is adapted to consider the spinodal decomposition of A2B6 semiconductor solid solutions. This approach is used to analyze the process of spinodal decomposition of ZnхCd1-хTe solid solution, which is accompanied by the appearance of the composition modulation effect during its low-temperature synthesis. Numerical simulations of the spinodal decomposition of the ZnхCd1-хTe solid solution are performed. It is shown that micro-variations of the material composition are related by the resonance phenomenon between the excess mixing energy and the energy of elastic strains arising in the inclusions of the new phase, which are coherently conjugated with the initial crystal lattice. It is revealed that such resonance phenomena are most intense when the conditions for the material synthesis are located in close proximity to the spinodal curves on the phase state diagram of the system.

scholarly journals Composition modulation in the GaxIni-xPyAs1-y - InP heterostructure during spinodal decomposition under the conditions of internal energy resonance

2021 ◽  
Vol 2103 (1) ◽  
pp. 012117
Author(s):  
V V Kuznetsov ◽  
P P Moskvin ◽  
S I Skurativskyi
Keyword(s):  
Numerical Simulation ◽  
Solid Solution ◽  
Thermodynamic Parameters ◽  
Spinodal Decomposition ◽  
Solid Solutions ◽  
System Of Differential Equations ◽  
Material Decomposition ◽  
Sphalerite Structure ◽  
Energy Resonance ◽  
Composition Modulation

Abstract The Cahn-Hilliard concepts are generalized and used to the description of the spinodal decomposition of A3B5 quaternary semiconductor solid solutions, when the mixing of components occurs simultaneously in the metallic and metalloid sublattices of the sphalerite structure. The resulting system of differential equations for material decomposition was used to describe the effect of composition modulation observed in the synthesis of GaxIn1-xPyAs1-y - InP heterostructures. Numerical simulation of the spinodal decomposition of the GaxIm-xPyAsuy solid solution is carried out. The intervals of the thermodynamic parameters of the technological process of the synthesis of structures, in which the effect of modulation of the composition should be manifested, are found.

Spinodal decomposition and composition modulation effect at the low-temperature synthesis of Ax3B1-x3C5 semiconductor solid solutions

2019 ◽  
Vol 510 ◽  
pp. 40-46 ◽  
Author(s):  
Pavel P. Moskvin ◽  
Sergii I. Skurativskyi ◽  
Oleksandr P. Kravchenko ◽  
Galyna V. Skyba ◽  
Hennadii V. Shapovalov
Keyword(s):  
Low Temperature ◽  
Spinodal Decomposition ◽  
Solid Solutions ◽  
Modulation Effect ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
Composition Modulation

Evidence for Instability in Pb1-x EuxTe Alloys

1987 ◽  
Vol 103 ◽  
Author(s):  
L. Salamanca-Young ◽  
M. Wuttig ◽  
D. L. Partin ◽  
J. Heremans
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Transmission Electron Microscopy ◽  
Molecular Beam Epitaxy ◽  
Spinodal Decomposition ◽  
Solid Solutions ◽  
Lattice Spacing ◽  
Molecular Beam ◽  
Transmission Electron ◽  
Modulated Structures

ABSTRACTWe have used transmission electron microscopy to study the structure of Pb1-xEuxTe alloys grown by molecular beam epitaxy. We have observed ordered solid solutions of the Pb1-x EuxTe alloys as well as spinodal decomposition for 0.35≤x<0.75. The spinodal decomposition corresponds to a modulation of both the composition and the lattice spacing of the Pb1-x EuxTe alloy. These modulated structures have periodicities of ∼18Å along the <111> and <110> directions and indicate that the solid solution of Pb1-x Eux Te is unstable in this range of compositions.

scholarly journals Synthesis of Ce1−xPdxO2−δ Solid Solution in Molten Nitrate

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 640
Author(s):  
Hideaki Sasaki ◽  
Keisuke Sakamoto ◽  
Masami Mori ◽  
Tatsuaki Sakamoto
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Solid Solutions ◽  
Photoelectron Spectroscopy ◽  
Synthesis Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Co Precipitation ◽  
Ionic States

CeO2-based solid solutions in which Pd partially substitutes for Ce attract considerable attention, owing to their high catalytic performances. In this study, the solid solution (Ce1−xPdxO2−δ) with a high Pd content (x ~ 0.2) was synthesized through co-precipitation under oxidative conditions using molten nitrate, and its structure and thermal decomposition were examined. The characteristics of the solid solution, such as the change in a lattice constant, inhibition of sintering, and ionic states, were examined using X-ray diffraction (XRD), scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM−EDS), transmission electron microscopy (TEM)−EDS, and X-ray photoelectron spectroscopy (XPS). The synthesis method proposed in this study appears suitable for the easy preparation of CeO2 solid solutions with a high Pd content.

Electron microprobe study of turquoise-group solid solutions in the Neyshabour and Meydook mines, northeast and southern Iran

2020 ◽  
Vol 58 (1) ◽  
pp. 71-83
Author(s):  
Elahe Mansouri Gandomani ◽  
Nematollah Rashidnejad-Omran ◽  
Amir Emamjomeh ◽  
Pietro Vignola ◽  
Tahereh Hashemzadeh
Keyword(s):  
Solid Solution ◽  
Solid Solutions ◽  
Electron Microprobe ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Major Elements ◽  
Point Of View ◽  
Chemical Compositions ◽  
Light Blue ◽  
Quaternary Solid Solution

ABSTRACT Turquoise, CuAl6(PO4)4(OH)8·4H2O, belongs to the turquoise group, which consists of turquoise, chalcosiderite, aheylite, faustite, planerite, and UM1981-32-PO:FeH. In order to study turquoise-group solid solutions in samples from the Neyshabour and Meydook mines, 17 samples were selected and investigated using electron probe microanalysis. In addition, their major elements were compared in order to evaluate the feasibility of distinguishing the provenance of Persian turquoises. The electron microprobe data show that the studied samples are not constituted of pure turquoise (or any other pure endmember) and belong, from the chemical point of view, to turquoise-group solid solutions. In a turquoise–planerite–chalcosiderite–unknown mineral quaternary solid solution diagram, the chemical compositions of the analyzed samples lie along the turquoise–planerite line with minor involvement of chalcosiderite and the unknown mineral. Among light blue samples with varying hues and saturations from both studied areas, planerite is more abundant among samples from Meydook compared with samples from Neyshabour. Nevertheless, not all the light blue samples are planerite. This study demonstrates that distinguishing the deposit of origin for isochromatic blue and green turquoises, based on electron probe microanalysis method and constitutive major elements, is not possible.

Epitaxial Solid-Solution Films of Immiscible MgO and CaO

1994 ◽  
Vol 341 ◽  
Author(s):  
E. S. Hellman ◽  
E. H. Hartford
Keyword(s):  
Solid Solution ◽  
Molecular Beam Epitaxy ◽  
Lattice Constant ◽  
Solid Solutions ◽  
Molecular Beam ◽  
Building Blocks ◽  
Layer Growth ◽  
Growth Mode ◽  
Miscibility Gap ◽  
Layer By Layer

AbstractMetastable solid-solutions in the MgO-CaO system grow readily on MgO at 300°C by molecular beam epitaxy. We observe RHEED oscillations indicating a layer-by-layer growth mode; in-plane orientation can be described by the Matthews theory of island rotations. Although some films start to unmix at 500°C, others have been observed to be stable up to 900°C. The Mgl-xCaxO solid solutions grow despite a larger miscibility gap in this system than in any system for which epitaxial solid solutions have been grown. We describe attempts to use these materials as adjustable-lattice constant epitaxial building blocks

Cationic Substitutions in Sphalerite from the Porgera Mine, Papua New Guinea

2021 ◽  
Author(s):  
Christopher H. Ingles ◽  
John A. Mavrogenes
Keyword(s):  
Solid Solution ◽  
Papua New Guinea ◽  
Solid Solutions ◽  
Inductively Coupled Plasma ◽  
New Guinea ◽  
Inductively Coupled ◽  
Cationic Substitution ◽  
Plasma Mass Spectrometry ◽  
Positive Correlations

ABSTRACT Laser ablation-inductively coupled plasma-mass spectrometry was used to traverse hydrothermal vein sphalerite from different ore-forming stages of the Porgera Au-Ag mine, Papua New Guinea. Elements were measured in situ over the growth of crystals to investigate the greatly varying concentrations of cations in sphalerite and their positions in the lattice. Traverse profiles for 16 elements were obtained and aligned to transmitted light images where possible. Each sample contained an array of elements, with many displaying orders of magnitude concentration differences. Results show the simultaneous incorporation of Cu and Sn in sphalerite, as well as Cu and Ag, In and Sn, As and Sb, Fe and Mn, and Cu and Ga. The relation [4Zn2+ ↔ 2Cu+ + Sn2+ + Sn4+] is proposed to explain the 1:1 Cu–Sn correlation. Further relations can be seen, including a Ga “ceiling” or Cu “floor”, where Ga incorporation becomes dependent on Cu concentrations. Furthermore, silver was also observed to correlate with Au, Mn, Ni, Pb, and Bi. Meta-stable solid solutions between pairs such as Cu, Ag; Fe, Mn; As, Sb; and In, Sn are also suggested. Each of these pairs are neighbors on the periodic table of elements, which suggests that simple solid solution can occur, and positive correlations for all four solid solutions were found in one sample alone. While the concept of charge-specific solid solutions in sphalerite has been discussed in the literature with reference to monovalent cations, the results presented herein also indicate solid solutions of higher oxidation states, containing many cations. Furthermore, while cations in charge-specific solid solutions have been proposed to compete for lattice sites in sphalerite, simultaneous in situ coupled concentrations at Porgera suggest otherwise. Cationic substitution equations displaying decimal ratios of each element in solid solution can then provide a novel method to distinguish between solid solution concentrations in different samples. For example, displaying 1:1 ratios of Cu–Ag and Sb–As: [2Zn2+ ↔ (Cu+0.5, Ag+0.5) + (As3+0.5, Sb3+0.5)], or for a 100:1 Fe–Mn ratio: [Zn2+ ↔ (Fe2+0.99, Mn2+0.01)].

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