scholarly journals Thermodynamic parameters depend on temperature with the influence of doping ratio of the crystal structure metals in extended X-Ray absorption fine structure

2021 ◽  
Vol 4 (10) ◽  
pp. 5-10
Author(s):  
Ba Duc Nguyen ◽  
Quang Tho Vu ◽  
Phi Hiep Trinh ◽  
Quynh Lam Nguyen Thi
Keyword(s):  
Crystal Structure ◽  
Fine Structure ◽  
Thermodynamic Parameters ◽  
Effective Potential ◽  
Single Pair ◽  
Face Centered Cubic ◽  
X Ray ◽  
Absorption Fine ◽  
X Ray Absorption ◽  
Doping Ratio

The effects of the doping ratio and temperature on the cumulants andthermodynamic parameters of crystal structure metals and their alloys wasinvestigated using the anharmonic correlated Einstein model, in extended X-ray absorption fine structure (EXAFS) spectra. We derived analytical expressions for the EXAFS cumulants, correlated Einstein frequency, Einstein temperature, and effective spring constant. We have considered parameters of the effective Morsepotential and the Debye-Waller factor depend on temperature and the effects of the doping ratio of face-centered-cubic (fcc) crystals of copper (Cu-Cu), silver (Ag-Ag), and hexagonal-close-packed (hcp) crystal of zinc (Zn-Zn), and their alloys of Cu-Ag and Cu-Zn. The derived anharmonic effective potential includes the contributions of all the nearest neighbors of the absorbing and scattering atoms. This accounts for three-dimensional interactions and the parameters of theMorse potential, to describe single-pair atomic interactions. The numericalresults of the EXAFS cumulants, thermodynamic parameters, and anharmonic effective potential agree reasonably with experiments and other theories.

Extended x-ray absorption fine structure study of incorporation of Bi and Pb atoms into the crystal structure of Ba4.5Nd9Ti18O54

1997 ◽  
Vol 12 (3) ◽  
pp. 799-804 ◽  
Author(s):  
M. Valant ◽  
I. Arčon ◽  
D. Suvorov ◽  
A. Kodre ◽  
T. Negas ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Fine Structure ◽  
Local Environment ◽  
Structure Study ◽  
X Ray ◽  
Absorption Fine ◽  
Exafs Study ◽  
X Ray Absorption

In the extended x-ray absorption fine structure (EXAFS) study of the local environment of Bi3+ and Pb2+ ions incorporated in Ba4.5Nd9Ti18O54, actual sites of Bi- and Pb-incorporation are determined. Evidence is given that dopant ions are not distributed randomly on all theoretically possible sites; Bi3+ selectively enters one out of three possible channels, corresponding to the sites x = 0.9484, y = 0.2500, z = 0.2939, and/or x = 0.0455, y = 0.2500, z = 0.6928 previously occupied by Nd3+, while Pb2+ selectively enters site x = 0.4940, y = 0.2500, and z = 0.4993 previously shared by Ba2+ and Nd3+.

Effect of the ligand in the crystal structure of zinc oxide: an x-ray powder diffraction, x-ray absorption near-edge structure, and an extended x-ray absorption fine structure study

2016 ◽  
Vol 6 (2) ◽  
pp. 93-97
Author(s):  
María de los A. Cepeda-Pérez ◽  
Cristina M. Reyes-Marte ◽  
Valerie Ann Carrasquillo ◽  
William A. Muñiz ◽  
Edgar J. Trujillo ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Zinc Oxide ◽  
Fine Structure ◽  
Powder Diffraction ◽  
Structure Study ◽  
Edge Structure ◽  
X Ray ◽  
Absorption Fine ◽  
Image Position ◽  
X Ray Absorption

Abstract

scholarly journals X-ray Absorption Fine Structure of bcc Crystals Studied Based on High-order Expanded Debye-Waller Factors

2017 ◽  
Vol 27 (1) ◽  
pp. 55
Author(s):  
Nguyen Van Hung ◽  
Trinh Thi Hue ◽  
Ha Dang Khoa ◽  
Tong Sy Tien
Keyword(s):  
Fine Structure ◽  
High Order ◽  
Atomic Interaction ◽  
Perturbation Approach ◽  
Single Pair ◽  
Many Body ◽  
X Ray ◽  
Absorption Fine ◽  
The Many ◽  
X Ray Absorption

In this work, X-ray absorption fine structure (XAFS) of bcc crystals and it Fourier transformmagnitude have been studied based on the anharmonic correlated Debye model high-order expandedDebye-Waller factors. The many-body effects are taken into account in the present one-dimensionalmodel based on the anharmonic effective potential that includes interactions of absorber andbackscatterer atoms with their first shell near neighbors, where Morse potential is assumed to describethe single-pair atomic interaction. Analytical expressions of four first temperature-dependent cumulantsof bcc crystals have been derived using the many-body perturbation approach. The obtained cumulantsare applied to calculating XAFS spectra and their Fourier transform magnitudes. Numerical results forFe are found to be in good agreement with experiment.

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