Summary
The crystal structure of aragonite (a=4.9611(4),b=7.9672(6),c=5.7407(4) Å, cell content: 4×CaCO3, space group:Pmcn) was refined with 1180 neutron diffraction data toR w =0.014 The atomic parameters of earlier X-ray refinements were essentially confirmed, but were now determined with considerably higher accuracy. The aplanarity of the carbonate group is 0.0280(5) Å, a value greater by 0.010 Å than that in dolomite.
Zusammenfassung
Die Kristallstruktur des Aragonits (a=4,9611(4),b=7,9672(6),c=5,7407(4) Å, Zellinhalt: 4×CaCO3, Raumgruppe:Pmcn) wurde mit 1180 Neutronenbeugungsdaten zu einemR w =0.014 verfeinert. Die Atomparameter früherer Röntgenverfeinerungen wurden im Prinzip bestätigt, nun jedoch mit beträchtlich höherer Genauigkeit bestimmt. Die Aplanarität der Karbonatgruppe beträgt 0.0280(5) Å, ein Wert, der um 0.010 Å größer ist als der im Dolomit.
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Jarosch, D., Heger, G. Neutron diffraction refinement of the crystal structure of aragonite. TMPM Tschermaks Petr. Mitt. 35, 127–131 (1986). https://doi.org/10.1007/BF01140844
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DOI: https://doi.org/10.1007/BF01140844