Network oxygen sites in calcium aluminoborosilicate glasses: Results from 17O{27Al} and 17O{11B} double resonance NMR
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چکیده
منابع مشابه
Oxygen triclusters in crystalline CaAl4O7 (grossite) and in calcium aluminosilicate glasses: 17O NMR
We present O MAS NMR data for crystalline calcium dialuminate (grossite), CaAl4O7 and monoaluminate, CaAl2O4. The first of these contains an oxygen tricluster site and serves as a model compound for sites of this type in aluminosilicate glasses. Tricluster site NMR parameters are distinct from those of bridging O atoms (Al-O-Al), allowing partial resolution in triple quantum MAS NMR spectra. Su...
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Structure factors for Ca (x/2)Al xSi 1-xO (2) glasses (x = 0,0.25,0. 5,0.67) extended to a wave vector of magnitude Q = 40 A (-1) have been obtained by high-energy x-ray diffraction. For the first time, it is possible to resolve the contributions of Si-O, Al-O, and Ca-O coordination polyhedra to the experimental atomic pair distribution functions. It has been found that the connectivity of Si/A...
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ژورنال
عنوان ژورنال: Journal of Non-Crystalline Solids
سال: 2016
ISSN: 0022-3093
DOI: 10.1016/j.jnoncrysol.2016.06.024