Superspace description of wagnerite-group minerals (Mg,Fe,Mn) 2 (PO 4 )(F,OH)

Lazic, Biljana; Armbruster, Thomas Michael; Chopin, Christian; Grew, Edward S.; Baronnet, Alain; Palatinus, Lukas (2014). Superspace description of wagnerite-group minerals (Mg,Fe,Mn) 2 (PO 4 )(F,OH). Acta crystallographica Section B, B70(2), pp. 243-258. International Union of Crystallography 10.1107/S2052520613031247

Preview

Text Armbruster.pdf - Published Version Available under License Publisher holds Copyright. Download (2MB) | Preview

Reinvestigation of more than 40 samples of minerals belonging to the wagnerite group (Mg, Fe, Mn)2(PO4)(F,OH) from diverse geological environments worldwide, using single-crystal X-ray diffraction analysis, showed that most crystals have incommensurate structures and, as such, are not adequately described with known polytype models (2b), (3b), (5b), (7b) and (9b). Therefore, we present here a unified superspace model for the structural description of periodically and aperiodically modulated wagnerite with the (3+1)-dimensional superspace group C2/c(0[beta]0)s0 based on the average triplite structure with cell parameters a [asymptotically equal to] 12.8, b [asymptotically equal to] 6.4, c [asymptotically equal to] 9.6 Å, [beta] [asymptotically equal to] 117° and the modulation vectors q = [beta]b*. The superspace approach provides a way of simple modelling of the positional and occupational modulation of Mg/Fe and F/OH in wagnerite. This allows direct comparison of crystal properties.

Interest & Impact

Downloads

370 since deposited on 11 Aug 2015
23 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item