Thermostructural and Elastic Properties of PbTe and Pb0.884Cd0.116Te: A Combined Low-Temperature and High-Pressure X-ray Diffraction Study of Cd-Substitution Effects

Rocksalt-type (Pb,Cd)Te belongs to IV–VI semiconductors exhibiting thermoelectric properties. With the aim of understanding of the influence of Cd substitution in PbTe on thermostructural and elastic properties, we studied PbTe and Pb0.884Cd0.116Te (i) at low temperatures (15 to 300 K) and (ii) at high pressures within the stability range of NaCl-type PbTe (up to 4.5 GPa). For crystal structure studies, powder and single crystal X-ray diffraction methods were used. Modeling of the data included the second-order Grüneisen approximation of the unit-cell-volume variation, V(T), the Debye expression describing the mean square atomic displacements (MSDs), <u2>(T), and Birch–Murnaghan equation of state (BMEOS). The fitting of the temperature-dependent diffraction data provided model variations of lattice parameter, the thermal expansion coefficient, and MSDs with temperature. A comparison of the MSD runs simulated for the PbTe and mixed (Pb,Cd)Te crystal leads to the confirmation of recent findings that the cation displacements are little affected by Cd substitution at the Pb site; whereas the Te displacements are markedly higher for the mixed crystal. Moreover, information about static disorder caused by Cd substitution is obtained. The calculations provided two independent ways to determine the values of the overall Debye temperature, θD. The resulting values differ only marginally, by no more than 1 K for PbTe and 7 K for Pb0.884Cd0.116Te crystals. The θD values for the cationic and anionic sublattices were determined. The Grüneisen parameter is found to be nearly independent of temperature. The variations of unit-cell size with rising pressure (the NaCl structure of Pb0.884Cd0.116Te sample was conserved), modeled with the BMEOS, provided the dependencies of the bulk modulus, K, on pressure for both crystals. The K0 value is 45.6(2.5) GPa for PbTe, whereas that for Pb0.884Cd0.116Te is significantly reduced, 33.5(2.8) GPa, showing that the lattice with fractional Cd substitution is less stiff than that of pure PbTe. The obtained experimental values of θD and K0 for Pb0.884Cd0.116Te are in line with the trends described in recently reported theoretical study for (Pb,Cd)Te mixed crystals.

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Structural, Electronic and Magnetic Properties of a Few Nanometer-Thick Superconducting NdBa2Cu3O7 Films

Nanomaterials ◽

10.3390/nano10040817 ◽

2020 ◽

Vol 10 (4) ◽

pp. 817

Author(s):

Marco Moretti Sala ◽

Marco Salluzzo ◽

Matteo Minola ◽

Gabriella Maria De Luca ◽

Greta Dellea ◽

...

Keyword(s):

Cuprate Superconductors ◽

Oxygen Deficiency ◽

Lattice Parameter ◽

Unit Cell ◽

Hole Doping ◽

X Ray Diffraction ◽

Thick Sample ◽

Transmission Microscopy ◽

X Ray ◽

Spectroscopic Signatures

Epitaxial films of high critical temperature ( T c ) cuprate superconductors preserve their transport properties even when their thickness is reduced to a few nanometers. However, when approaching the single crystalline unit cell (u.c.) of thickness, T c decreases and eventually, superconductivity is lost. Strain originating from the mismatch with the substrate, electronic reconstruction at the interface and alteration of the chemical composition and of doping can be the cause of such changes. Here, we use resonant inelastic x-ray scattering at the Cu L 3 edge to study the crystal field and spin excitations of NdBa 2 Cu 3 O 7 − x ultrathin films grown on SrTiO 3 , comparing 1, 2 and 80 u.c.-thick samples. We find that even at extremely low thicknesses, the strength of the in-plane superexchange interaction is mostly preserved, with just a slight decrease in the 1 u.c. with respect to the 80 u.c.-thick sample. We also observe spectroscopic signatures for a decrease of the hole-doping at low thickness, consistent with the expansion of the c-axis lattice parameter and oxygen deficiency in the chains of the first unit cell, determined by high-resolution transmission microscopy and x-ray diffraction.

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Determination of lattice parameter and elastic properties of porous silicon by X-ray diffraction

Journal of Crystal Growth ◽

10.1016/0022-0248(84)90111-8 ◽

1984 ◽

Vol 68 (3) ◽

pp. 727-732 ◽

Cited By ~ 186

Author(s):

K. Barla ◽

R. Herino ◽

G. Bomchil ◽

J.C. Pfister ◽

A. Freund

Keyword(s):

Porous Silicon ◽

Elastic Properties ◽

Lattice Parameter ◽

X Ray Diffraction ◽

X Ray

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Crystallographic and optical study of PbHfO3 crystals

Journal of Applied Crystallography ◽

10.1107/s1600576717000309 ◽

2017 ◽

Vol 50 (2) ◽

pp. 378-384 ◽

Cited By ~ 11

Author(s):

S. Huband ◽

A. M. Glazer ◽

K. Roleder ◽

A. Majchrowski ◽

P. A. Thomas

Keyword(s):

Intermediate Phase ◽

Lattice Parameter ◽

High Temperature Phase ◽

Unit Cell ◽

Tetragonal Symmetry ◽

Orthorhombic Symmetry ◽

Temperature Phase ◽

Optical Study ◽

X Ray Diffraction ◽

X Ray

The symmetry of the intermediate high-temperature phase of PbHfO3 has been determined unambiguously to be orthorhombic using a combination of high-resolution X-ray diffraction and birefringence imaging microscopy measurements of crystal plates. While lattice parameter measurements as a function of temperature in the intermediate phase are consistent with either orthorhombic or tetragonal symmetry, domain orientations observed in birefringence imaging microscopy measurements utilizing the Metripol system are only consistent with orthorhombic symmetry with the unit cell in the rhombic orientation of the pseudocubic unit cell.

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Relationship between the volume of the unit cell of hexagonal-close-packed Ti, hardness and oxygen content after α-case formation in Ti–6Al–2Sn–4Zr–2Mo–0.1Si alloy

Journal of Applied Crystallography ◽

10.1107/s1600576715022906 ◽

2016 ◽

Vol 49 (1) ◽

pp. 175-181 ◽

Cited By ~ 8

Author(s):

J. Baillieux ◽

D. Poquillon ◽

B. Malard

Keyword(s):

Cross Sections ◽

Oxygen Diffusion ◽

Lattice Parameter ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Electron Probe Microanalyzer ◽

Hexagonal Close Packed ◽

Linear Relationships ◽

Oxygen Gradients

In this study, the influence of oxygen diffusion on the physical properties of Ti–6Al–2Sn–4Zr–2Mo–0.1Si was examined. Measurements were carried out directly on sample cross sections which were preoxidized at high temperature. The lattice parameter evolution was measured using synchrotron X-ray diffraction and was coupled with microhardness and electron probe microanalyzer results with the aim of highlighting their relationships. The results show that the hardness and oxygen gradients along the oxygen diffusion zone in the alloy are similar to the evolution of the α-phase unit-cell volume quantified by X-ray diffraction. Linear relationships were found between these three parameters.

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Crystal structure of Ca1−xSrxZr4(PO4)6 (0≤x≤1)

Powder Diffraction ◽

10.1154/1.1643051 ◽

2004 ◽

Vol 19 (2) ◽

pp. 153-156 ◽

Cited By ~ 18

Author(s):

Werner Fischer ◽

Lorenz Singheiser ◽

Debabrata Basu ◽

Amit Dasgupta

Keyword(s):

Crystal Structure ◽

Solid Solution ◽

High Temperature ◽

Structural Transformation ◽

Powder Diffraction ◽

Room Temperature ◽

Lattice Parameter ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray

The crystal structure of several compounds of Ca1−xSrxZr4(PO4)6 ceramics has been investigated by X-ray powder diffraction at room temperature. All compounds form a solid solution with a unique unit cell. While the lattice parameter a of the hexagonal unit cell decreases of about 0.9% with increasing Sr content only slightly, it considerably elongates in c direction (2.8%). No structural transformation has been observed by high-temperature X-ray diffraction up to 1000 °C.

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X-Ray Diffraction Study of BaNd2CuO5 at High Pressures

Advances in X-ray Analysis ◽

10.1154/s0376030800018486 ◽

1994 ◽

Vol 38 ◽

pp. 741-747

Author(s):

Winnie Wong-Ng ◽

Gasper J. Piermarini ◽

Marcia R. Gallas

Keyword(s):

High Pressures ◽

Unit Cell ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Tetragonal Unit Cell ◽

Least Squares Fit ◽

Diamond Anvil ◽

Volume Compression

Abstract The volume compression of BaNd2CuO5 has been measured to 8.7 GPa utilizing a diamond anvil high pressure eel and energy dispersive x-ray powder diffraction. The pressure dependence of the volume of the tetragonal unit cell is linear and follows the equation V = -1.6I5P + 260.622 determined by a least-squares fit of the data. Compression of the unit cell parameters of BaNd2CuO5 exhibit isotropic behavior within our experimental error. From the observed data, the bulk modulus of BaNd2CuO5 is determined to be 161 ± 6 GPa and the Young's modulus is estimated to be 193 ± 6 GPa. No evidence of a pressure-induced phase transformation in BaNd2CuO5 was found in the pressure range studied.

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FexCu1-xBa2YCu2O7+y SUPERCONDUCTORS SYNTHESIZED BY HIGH PRESSURE

International Journal of Modern Physics B ◽

10.1142/s021797920502827x ◽

2005 ◽

Vol 19 (01n03) ◽

pp. 221-223 ◽

Cited By ~ 3

Author(s):

Y. H. LIU ◽

G. C. CHE ◽

K. Q. LI ◽

Z. X. ZHAO ◽

Z. Q. KOU ◽

...

Keyword(s):

High Pressure ◽

Cell Volume ◽

Oxygen Content ◽

Unit Cell Volume ◽

Ambient Pressure ◽

Lattice Parameter ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Coordination

Systematic studies of x-ray diffraction(XRD), superconductivity and Mössbauer effect on Fe x Cu 1-x Ba 2 YCu 2 O 7+y ( x =0.00~0.70) superconductors synthesized by high pressure (HP) were summarized. All the HP-samples have tetragonal structure, smaller lattice parameter c and unit-cell volume than the AM-samples (synthesized by ambient pressure). The HP-samples have higher oxygen content than the AM-samples. Moreover, for the HP-sample with x =0.5, all of the Fe located in the CuO x chains have fivefold-oxygen coordination.

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X-ray diffraction and Raman studies of beryllium: Static and elastic properties at high pressures

Physical Review B ◽

10.1103/physrevb.72.094113 ◽

2005 ◽

Vol 72 (9) ◽

Cited By ~ 31

Author(s):

W. J. Evans ◽

M. J. Lipp ◽

H. Cynn ◽

C. S. Yoo ◽

M. Somayazulu ◽

...

Keyword(s):

Elastic Properties ◽

High Pressures ◽

X Ray Diffraction ◽

X Ray

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Fabrication and study the effect of the laser on the properties of the compound Tl2-xHgxBa2-ySryCa2Cu3O10+δ superconductor

Ibn AL- Haitham Journal For Pure and Applied Science ◽

10.30526/2017.ihsciconf.1789 ◽

2018 ◽

pp. 168

Author(s):

A. Kareem Dahash Ali ◽

Nihad Ali Shafeek

Keyword(s):

Transition Temperature ◽

Solid State ◽

Hydrostatic Pressure ◽

Electrical Properties ◽

Co2 Laser ◽

Temperature Shift ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Structural And Electrical Properties

This study included the fabrication of compound (Tl2-xHgxBa2-ySryCa2Cu3O10+δ) in a manner solid state and under hydrostatic pressure ( 8 ton/cm2) and temperature annealing(850°C), and determine the effect of the laser on the structural and electrical properties elements in the compound, and various concentrations of x where (x= 0.1,0.2,0.3 ). Observed by testing the XRD The best ratio of compensation for x is 0.2 as the value of a = b = 5.3899 (A °), c = 36.21 (A °) show that the installation of four-wheel-based type and that the best temperature shift is TC= 142 K .When you shine a CO2 laser on the models in order to recognize the effect of the laser on these models showed the study of X-ray diffraction of these samples when preparing models with different concentrations of the values of x, the best ratio of compensation is 0.2 which showed an increase in the values of the dimensions of the unit cell a=b = 5.3929 (A °), c = 36.238 (A°). And the best transition temperature after shedding laser is TC=144 K.

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X-ray Diffraction Analysis and Williamson-Hall Method in USDM Model for Estimating More Accurate Values of Stress-Strain of Unit Cell and Super Cells (2 × 2 × 2) of Hydroxyapatite, Confirmed by Ultrasonic Pulse-Echo Test

Materials ◽

10.3390/ma14112949 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2949

Author(s):

Marzieh Rabiei ◽

Arvydas Palevicius ◽

Amir Dashti ◽

Sohrab Nasiri ◽

Ahmad Monshi ◽

...

Keyword(s):

Young’S Modulus ◽

Young's Modulus ◽

Ultrasonic Pulse ◽

High Accuracy ◽

Unit Cell ◽

Deformation Model ◽

X Ray Diffraction ◽

Uniform Deformation ◽

X Ray ◽

Pulse Echo

Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern or they extracted Young’s modulus from the literature. Therefore, these values are not representative of all peaks derived from X-ray diffraction; as a result, these values are not estimated with high accuracy. Nevertheless, in the current study, the W-H method is used considering the all diffracted planes of the unit cell and super cells (2 × 2 × 2) of Hydroxyapatite (HA), and a new method with the high accuracy of the W-H method in the USDM model is presented to calculate stress (σ) and strain (ε). The accounting for the planar density of atoms is the novelty of this work. Furthermore, the ultrasonic pulse-echo test is performed for the validation of the novelty assumptions.

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