0379239 - FZÚ 2013 RIV GB eng J - Journal Article
Plášil, J. - Fejfarová, Karla - Skála, Roman - Škoda, R. - Meisser, N. - Hloušek, J. - Císařová, I. - Dušek, Michal - Veselovský, F. - Čejka, J. - Sejkora, J. - Ondruš, P.
The crystal chemistry of the uranyl carbonate mineral grimselite, (K,Na)₃Na[(UO₂)(CO₃)₃](H₂O), from Jáchymov, Czech Republic.
Mineralogical Magazine. Roč. 76, č. 3 (2012), s. 443-453. ISSN 0026-461X. E-ISSN 1471-8022
R&D Projects: GA ČR(CZ) GAP204/11/0809
Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z30130516
Keywords : uranyl carbonate * grimselite * crystal structure * chemical composition * Jáchymov
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 2.212, year: 2012 ; AIS: 0.727, rok: 2012
DOI: https://doi.org/10.1180/minmag.2012.076.3.01

Two crystals of the uranyl carbonate mineral grimselite, ideally K3Na[(UO2)(CO3)3](H2O), from Jáchymov in the Czech Republic were studied by single-crystal X-ray diffraction and electron-probe microanalysis. One crystal has considerably more Na than the ideal chemical composition due to substitution of Na into KO8 polyhedra; the composition of the other crystal is nearer to ideal, and similar to synthetic grimselite. The presence of Na atoms in KO8 polyhedra, which are located in channels in the crystal structure, reduces their volume, and as a result the unit-cell volume also decreases. Structure refinement shows that the formula for the sample with the anomalously high Na content is (K2.43Na0.57)<Σ3.00Na[(UO2)(CO3)3](H2O).
Permanent Link: http://hdl.handle.net/11104/0210494