کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6305856 | 1307326 | 2014 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The effect of valence state and site geometry on Cr L3,2 electron energy-loss spectra of Cr-bearing oxidic compounds
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
ژئوشیمی و پترولوژی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Chromium L3,2 energy loss near-edge structures (ELNES) of nine chromium compounds were measured in a transmission electron microscope to study the effect of valence state and site geometry of chromium on spectral features. The compounds studied represent a set of standards with given valence state and coordination. The chromium coordination is either octahedral or tetrahedral with different degree of distortion. The distortion of polyhedra results in a loss of the fine detail of spectral features in Cr L3,2 ELNES spectra. The effect of valence state manifests in a systematic chemical shift of the ELNES spectra by about 2Â eV per oxidation state for octahedrally coordinated Cr and 0.4-1.4Â eV per oxidation state for tetrahedrally coordinated Cr. On the basis of collected Cr L3,2 ELNES spectra we propose a simple quantification technique for the determination of chromium oxidation state in oxidic compounds which is independent of the coordination.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemie der Erde - Geochemistry - Volume 74, Issue 3, October 2014, Pages 497-505
Journal: Chemie der Erde - Geochemistry - Volume 74, Issue 3, October 2014, Pages 497-505
نویسندگان
Emil Stoyanov, Falko Langenhorst,