The Fe{sup 2+}/Fe{sup 3+} ratio in natural and heat-treated iron-rich eudialytes

Journal Article · Tue Mar 15 04:00:00 EDT 2011 · Crystallography Reports

DOI:https://doi.org/10.1134/S1063774511020167· OSTI ID:22054310

Aksenov, S M; Rozenberg, K A; Verin, I A ^[1]

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1. Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

The structures of natural iron-rich eudialyte (specimen 3458 from the Khibiny massif, the Kola Peninsula) and two heat-treated samples of this mineral calcined at 700 and 800 Degree-Sign C were determined by X-ray diffraction. The trigonal unit-cell parameters (sp. gr. R3m) are as follows: a = 14.2645(1) Angstrom-Sign , c = 29.9635(5) Angstrom-Sign ; a = 14.1307(1) Angstrom-Sign , c = 30.1229(3) Angstrom-Sign ; a = 14.1921(2) Angstrom-Sign , c = 30.2417(5) Angstrom-Sign , respectively. It was found that Fe{sup 3+} ions in the calcined eudialytes, as well as impurities in the starting specimen, occupy the square-pyramidal Fe{sup 3+}(V) sites, whereas Fe{sup 2+} ions are in the planar-tetragonal Fe{sup 2+}(IV) sites.

• OSTI ID: 22054310
• Journal Information: Crystallography Reports, Journal Name: Crystallography Reports Journal Issue: 2 Vol. 56; ISSN CYSTE3; ISSN 1063-7745
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HEAT TREATMENTS
IMPURITIES
IRON IONS
SILICATE MINERALS
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
TRIGONAL LATTICES
X-RAY DIFFRACTION