On the High-Temperature Phase Transition of GdSiGe.
The first-order monoclinic-to-orthorhombic (β→γ) phase transition of the giant magnetocaloric material GdSiGe was studied using in situ high-temperature single-crystal X-ray diffraction. A special crystal mounting procedure was developed to avoid crystal contamination by oxygen or nitrogen at high t...
| Publicado en: | Journal of the American Chemical Society Vol. 127; no. 1; pp. 317 - 325 |
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| Autores principales: | , , , |
| Formato: | Artículo |
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American Chemical Society
1/12/2005
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=15998379&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 15998379 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 1/12/2005 vid: 127 iid: 1 pid: 997 pub: American Chemical Society artinfo: ui: 15998379 10.1021/ja048679k ppf: 317 ppct: 8 formats: tig: atl: On the High-Temperature Phase Transition of GdSiGe. aug: au: Mozharivskyj, Yurij Pecharsky, Alexandra O. Pecharsky, Vitalij K. Miiler, Gordon J. affil: Ames Laboratory, Materials and Engineering Physics Program, Iowa State University, Ames, Iowa 50011-3020. Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011-2300. Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111. su: Physical & theoretical chemistry Oxygen Nitrogen Optical diffraction High temperatures Heat sug: subj: Physical & theoretical chemistry Oxygen Nitrogen Optical diffraction High temperatures Heat ab: The first-order monoclinic-to-orthorhombic (β→γ) phase transition of the giant magnetocaloric material GdSiGe was studied using in situ high-temperature single-crystal X-ray diffraction. A special crystal mounting procedure was developed to avoid crystal contamination by oxygen or nitrogen at high temperatures. The elastic β→γ transformation occurs at 300-320 °C during heating, and it is reversible during fast and slow heating and slow cooling but irreversible during rapid cooling. Contrary to theoretical predictions, the macroscopic distribution of the Si and Ge atoms remains the same in both the orthorhombic γ-polymorph and the monoclinic β-phase. It appears that interstitial impurities may affect stability of both the monoclinic and orthorhombic phases. In the presence of small amounts of air, the β→γ transformation is complete only at 600 °C. The interslab voids, which can accommodate impurity atoms, have been located in the structure, and an effect of partially filling these voids with oxygen or nitrogen atoms on the β→γ transition is discussed. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2005 holdings: @attributes: islocal: N |
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