%0 Journal Article
%A Zietlow, Peter
%A Beirau, Tobias
%A Groat, Lee
%A Paulmann, Carsten
%A Bismayer, Ulrich
%T <sup>29</sup>Si MAS NMR spectroscopy and synchrotron XRD study of metamict Cardiff titanite
%J Zeitschrift für Kristallographie / Crystalline materials
%V 229
%N 8
%@ 0044-2968
%C Berlin
%I De @Gruyter
%M PUBDB-2014-04232
%M BMBF-Projekt 05K13GU1
%P 551 - 554
%D 2014
%X Metamict titanite from the Cardiff uranium mine(M28696) in Ontario, Canada, has been analyzed using29Si magic angle spinning nuclear magnetic resonancespectroscopy (MAS NMR). A broad Gaussian shaped NMRsignal at –81 ppm occurs at room temperature resultingfrom the mainly locally ordered metamict structural state.NMR signals were obtained at room temperature andafter annealing at 600, 950, 1220 and 1470 K. Because ofincreasing crystallinity the full width at half maximum(FWHM) decreased from 24 ppm to 20 ppm, respectivelyusing a pseudo-Voigt fit. For comparison highly-crystallinetitanite from Rauris showed an NMR signal at –79.3 ppmwith FWHM of 4.1 ppm and an almost Lorentzian profilebecause of its good long range order. Integrating synchrotronX-ray diffraction (XRD) signals of Cardiff titaniteshow an increase of the crystallographic long range orderat annealing temperatures considerably lower than thelocal ordering seen by NMR.
%F PUB:(DE-HGF)29 ; PUB:(DE-HGF)16
%9 ReportJournal Article
%U <Go to ISI:>//WOS:000343696900002
%R 10.1515/zkri-2014-1738
%U https://bib-pubdb1.desy.de/record/192655