## Abstract ^207^Pb solidβstate NMR studies have been conducted on binary leadβgroup 16 and mixed transitionβmetal/lead group 16 materials, correlating the NMR chemical shifts of the materials with their structures. The experimental results show that the ^207^Pb chemical shifts are strongly influen
NMR-spectroscopic study of 207Pb in pure and barium diluted lead phosphate
β Scribed by Michael Fechtelkord; Ulrich Bismayer
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 413 KB
- Volume
- 11
- Category
- Article
- ISSN
- 0926-2040
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β¦ Synopsis
31P and 207Pb MAS and static 207Pb NMR spectra of Pb3(PO4)2 and (Pb1-xBa(x))3(PO4)2 (x = 0.08, 0.12) are analysed. The resonances stemming from different cation sites are correlated with the corresponding local symmetry and their oxygen neighbours. The coordination sphere of Pb(1) consists of 12 oxygen atoms and shows characteristics of a near-axial arrangement with a comparatively low anisotropy. The tenfold coordinated Pb(2) atoms are located in a more anisotropically-coordinated site. In Pb-diluted lead phosphate crystals the Pb(2) positions appear to be preferentially substituted by barium. There are indications that the cation distributions in the diluted samples are inhomogeneous. Furthermore, 31P MAS NMR experiments indicate a single phosphorus position.
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