کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1332140 979030 2006 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Crystal structure of the pyrochlore oxide superconductor KOs2O6
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Crystal structure of the pyrochlore oxide superconductor KOs2O6
چکیده انگلیسی

We report the single-crystal X-ray analysis of the structure of the pyrochlore oxide superconductor KOs2O6. The structure was identified as the ββ-pyrochlore structure with space group Fd3¯m and lattice constant a=10.089(2)Å at 300K: the K atom is located at the 8b8b site, not at the 16d16d site as in conventional pyrochlore oxides. We found an anomalously large atomic displacement parameter Uiso=0.0735(8)Å2 at 300K for the K cation, which suggests that the K cation weakly bound to an oversized Os12O18 cage exhibits intensive rattling, as recently observed for clathrate compounds. The rattling of A cations is a common feature in the series of ββ-pyrochlore oxide superconductors AOs2O6 (A=CsA=Cs, Rb and K), and is greatest for the smallest K cation.

Crystal structure of ββ-pyrochlore oxide KOs2O6. Corner-shared OsO6 octahedra form a three-dimensional network involving large atomic cage, and a K atom in each cage constitutes a ’hypothetical’ diamond lattice.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Solid State Chemistry - Volume 179, Issue 1, January 2006, Pages 336–340
نویسندگان
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