Disorder in natrolites; structure determinations of three disordered natrolites and one lithium-exchanged disordered natrolite

Saved in:
Online Access: Get full text
doi: 10.1127/ejm/2/6/0799
Authors:Krogh Andersen, Erik; Krogh Andersen, Inger G.; Ploug-Sorensen, Gudrun
Author Affiliations:Primary:
Odense Univ., Dep. Chem., Odense, Denmark
Volume Title:European Journal of Mineralogy
Source:European Journal of Mineralogy, 2(6), p.799-807. Publisher: Schweizerbart'sche Verlagsbuchhandlung (Nägele u. Obermiller), Stuttgart, Federal Republic of Germany. ISSN: 0935-1221
Publication Date:1990
Note:In English. 20 refs.; illus. incl. 9 tables
Summary:Single crystal diffraction studies of three natrolite specimens from Uzabanya, Hungary (Na I, Na III, and Na II) were undertaken. In the study of Na I (a = 18.305(3), b = 18.632(3), c = 6.589(2) A), 783 diffraction intensities were used (CAD-4 diffractometer, MoKα radiation (λMoKα = 0.71069 A)) and the structure was refined to R (unweighted) = 0.020, R (weighted) = 0.026. In the study of Na III (a = 18.367(2), b = 18.583(1), c = 6.599(3) A), 1304 diffraction intensities were used and the structure was refined to R (unweighted) = 0.025, R (weighted) = 0.027. In the study of Na II (a = 18.372(2), b = 18.576(2), c = 6.606(3) A), 847 diffraction intensities were used and the structure was refined to R (unweighted) = 0.018, R (weighted) = 0.026. The three specimens differ in cell constants and in average Si-O and Al-O distances (in Na I Si-O(av)= 1.621 A, Al-O(av) = 1.739 A; in Na III Si-O(av) = 1.636 A, Al-O(av)= 1.716 A; in Na II Si-O(av) = 1.638 A, Al-O(av)= 1.713 A). The difference in cell constants and in Si-O and Al-O distances are related to the Si/Al order in the materials. Crystals of Na II type were exchanged to the lithium form (Li II) in molten lithium nitrate (the crystals remained preserved). Single crystal studies of the exchanged material (a = 17.704(4), b = 18.540(5), c = 6.495(2) A) used 775 diffraction intensities. The structure is similar to the structure of the sodium form. The structure was refined to R (unweighted) = 0.029, R (weighted) = 0.041. The lithium coordination is discussed.
Subjects:Alkali metals; Coordination; Crystal structure; Framework silicates; Ion exchange; Lithium; Metals; Natrolite; Order-disorder; Refinement; Silicates; Zeolite group; Central Europe; Europe; Hungary
Abstract Numbers:91M/2622
Record ID:1994008248
Copyright Information:GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Geoline, Bundesanstalt fur Geowissenschaften und Rohstoffe, Hanover, Germany
Tags: Add Tag
No Tags, Be the first to tag this record!
Be the first to leave a comment!
You must be logged in first