Received 16 July 2008
A natural sample of perovskite (calcium caesium sodium iron titanium oxide) from the Tapira Alkaline Complex in southeastern Brazil was found by electron microprobe analysis to have the chemical formula (Ca2+0.95 (1)Ce3+0.011 (2)Na+0.010 (4))(Fe3+0.022 (2)Ti4+0.98 (1))O2-3 and by IR spectroscopy to be an anhydrous mineral. Oxygen anions are arranged around Ti4+ in an almost perfect octahedron and around Ca2+ in a distorted 12-fold polyhedron.
For related literature, see: Banfield & Veblen (1992); Beran et al. (1996); Chakhmouradian & Mitchell (1998); Haggerty & Mariano (1983); Kay & Bailey (1957); Lloyd & Bailey (1991); Mariano & Mitchell (1991); Seer & Moraes (1988); Sgarbi & Gaspar (1995); Sgarbi & Valença (1994); Soubies et al. (1991).
Data collection: XSCANS (Siemens, 1991); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalMaker (CrystalMaker, 2007); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: MG2053 ).
The authors are grateful to Dr José Affonso Brod, University of Brasília, Brazil, for providing the perovskite samples, and to Mr William T. Soares for the microprobe analysis. This work was supported by the Minas Gerais Foundation for Research Development, FAPEMIG (Grant CEX 1123/90). EGG is grateful to the Brazilian Science Research Council, CNPq, for providing a graduate fellowship.
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