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Title: Local atomic structure inheritance in Ag{sub 50}Sn{sub 50} melt

Abstract

Local structure inheritance signatures were observed during the alloying process of the Ag{sub 50}Sn{sub 50} melt, using high-temperature X-ray diffraction and ab initio molecular dynamics simulations. The coordination number N{sub m} around Ag atom is similar in the alloy and in pure Ag melts (N{sub m} ∼ 10), while, during the alloying process, the local structure around Sn atoms rearranges. Sn-Sn covalent bonds were substituted by Ag-Sn chemical bonds, and the total coordination number around Sn increases by about 70% as compared with those in the pure Sn melt. Changes in the electronic structure of the alloy have been studied by Ag and Sn K-edge X-ray absorption spectroscopy, as well as by calculations of the partial density of states. We propose that a leading mechanism for local structure inheritance in Ag{sub 50}Sn{sub 50} is due to s-p dehybridization of Sn and to the interplay between Sn-s and Ag-d electrons.

Authors:
; ; ; ; ; ; ;  [1]; ;  [2]
  1. Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China)
  2. Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China)
Publication Date:
OSTI Identifier:
22275661
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION SPECTROSCOPY; CHEMICAL BONDS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; COORDINATION NUMBER; ELECTRONIC STRUCTURE; ELECTRONS; INTERMETALLIC COMPOUNDS; MOLECULAR DYNAMICS METHOD; SILVER; TEMPERATURE DEPENDENCE; TIN; X-RAY DIFFRACTION; X-RAY SPECTROSCOPY

Citation Formats

Bai, Yanwen, Bian, Xiufang, E-mail: xfbian@sdu.edu.cn, Qin, Jingyu, Hu, Lina, Yang, Jianfei, Zhang, Kai, Zhao, Xiaolin, Yang, Chuncheng, Zhang, Shuo, and Huang, Yuying. Local atomic structure inheritance in Ag{sub 50}Sn{sub 50} melt. United States: N. p., 2014. Web. doi:10.1063/1.4863125.
Bai, Yanwen, Bian, Xiufang, E-mail: xfbian@sdu.edu.cn, Qin, Jingyu, Hu, Lina, Yang, Jianfei, Zhang, Kai, Zhao, Xiaolin, Yang, Chuncheng, Zhang, Shuo, & Huang, Yuying. Local atomic structure inheritance in Ag{sub 50}Sn{sub 50} melt. United States. doi:10.1063/1.4863125.
Bai, Yanwen, Bian, Xiufang, E-mail: xfbian@sdu.edu.cn, Qin, Jingyu, Hu, Lina, Yang, Jianfei, Zhang, Kai, Zhao, Xiaolin, Yang, Chuncheng, Zhang, Shuo, and Huang, Yuying. Tue . "Local atomic structure inheritance in Ag{sub 50}Sn{sub 50} melt". United States. doi:10.1063/1.4863125.
@article{osti_22275661,
title = {Local atomic structure inheritance in Ag{sub 50}Sn{sub 50} melt},
author = {Bai, Yanwen and Bian, Xiufang, E-mail: xfbian@sdu.edu.cn and Qin, Jingyu and Hu, Lina and Yang, Jianfei and Zhang, Kai and Zhao, Xiaolin and Yang, Chuncheng and Zhang, Shuo and Huang, Yuying},
abstractNote = {Local structure inheritance signatures were observed during the alloying process of the Ag{sub 50}Sn{sub 50} melt, using high-temperature X-ray diffraction and ab initio molecular dynamics simulations. The coordination number N{sub m} around Ag atom is similar in the alloy and in pure Ag melts (N{sub m} ∼ 10), while, during the alloying process, the local structure around Sn atoms rearranges. Sn-Sn covalent bonds were substituted by Ag-Sn chemical bonds, and the total coordination number around Sn increases by about 70% as compared with those in the pure Sn melt. Changes in the electronic structure of the alloy have been studied by Ag and Sn K-edge X-ray absorption spectroscopy, as well as by calculations of the partial density of states. We propose that a leading mechanism for local structure inheritance in Ag{sub 50}Sn{sub 50} is due to s-p dehybridization of Sn and to the interplay between Sn-s and Ag-d electrons.},
doi = {10.1063/1.4863125},
journal = {Journal of Applied Physics},
number = 4,
volume = 115,
place = {United States},
year = {Tue Jan 28 00:00:00 EST 2014},
month = {Tue Jan 28 00:00:00 EST 2014}
}
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  • Twenty new ternary representatives of the Gd 14Ag 51 structure type have been synthesized within the R-Au-M family (R = Y, La–Nd, Sm–Tb, Ho, Er, Yb, Lu; M = Al, Ga, Ge, In, Sn, Sb, Bi) using solid state synthesis techniques. The list of post transition metals (M) involved in the formation of this type of structure could be augmented by five new representatives. All compounds crystallize in the hexagonal space group P6/m (#175) with the unit cell ranges of a = 12.3136(2)–12.918(1) Å and c = 8.9967(3)–9.385(1) Å, and incorporate different degrees of Au/M mixing. The involvement of themore » post transition element in the structure varies from one to another compound both qualitatively and quantitatively. A rather significant phase width can be expected for the majority of compounds, however, not without exclusions. The distribution of the post transition metals within the structure has been analyzed via single crystal X-ray diffraction. While the positional disorder of one near-origin Au position is expectable for all compounds due to steric reasons, two specimens show an obvious deviation from the others including another Au position split along the c axis. Lastly, possible factors affecting this behavior are discussed.« less
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