کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9803182 | 1516463 | 2005 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Ce-valence state and hydrogen-induced volume effects in Ce-based intermetallic compounds and their hydrides
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
An average Ce-valence state (v) of two types of Ce-containing intermetallic compounds, equiatomic CeNiX (X= Al, Ga, Sn) and CeM3 (M= Ni, Co, Mn), and their hydrides was estimated from X-ray absorption spectroscopy (XAS) and analysed in parallel with hydrogen-induced volume changes on hydrogenation. The largest valence states in the initial compounds were found in CeM3(v=3.32â3.36) followed by CeNiAl1âxGax(v=3.25â3.27). This contrasts to CeNiSn, which is close to a pure trivalent state (v=3.07). On hydrogenation, a conversion from mixed-valent CeNiAl1âxGax, x=0.5, 1, to pure CeIII hydrides takes place (ÎV /V=19.6â20.0 %). In CeNiSnDz (z=1, 1.8, ÎV/V=3.0, 8.0%) the changes in the valence state towards CeIII are very small. The situation for the CeM3-hydrides is complex. For CeNi3D2.8, CeNi2.75Mn0.25D3.4 and CeCo3D3.4 (ÎV /V=24â32%) where rather similar electronic properties can be expected, a decrease in the contribution of CeIV for CeNi3D3 and CeNi2.75Mn0.25D3.4 (v=3.18 and 3.12, respectively) contrasts to the behaviour of CeCo3D3.4 where the hydrogen induced valence change is very small (v=3.32).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Alloys and Compounds - Volumes 404â406, 8 December 2005, Pages 144-149
Journal: Journal of Alloys and Compounds - Volumes 404â406, 8 December 2005, Pages 144-149
نویسندگان
M. Stange, V. Paul-Boncour, M. Latroche, A. Percheron-Guégan, O. Isnard, V.A. Yartys,