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Crystal structure of Al5O3N3 (15R)

Published online by Cambridge University Press:  25 January 2017

Jacek Podwórny*
Affiliation:
Refractory Materials Division in Gliwice, Institute of Ceramics and Building Materials, ul. Toszecka 99, 44-101 Gliwice, Poland
Alicja Pawełek
Affiliation:
Refractory Materials Division in Gliwice, Institute of Ceramics and Building Materials, ul. Toszecka 99, 44-101 Gliwice, Poland
Jerzy Czechowski
Affiliation:
Refractory Materials Division in Gliwice, Institute of Ceramics and Building Materials, ul. Toszecka 99, 44-101 Gliwice, Poland
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

Having synthesised an AlON-bonded ceramic corundum material, Al5O3N3 (15R) polytype coexisting with α-Al2O3 was identified. The sample was prepared from an alumina-rich mixture of Al2O3 and AlN substrates and fired at 1650 °C in a nitrogen atmosphere. Using the X-ray external standard quantitative method, one of the reaction products, α-Al2O3, was quantified. From the remaining substrates the stoichiometric composition of the second phase was calculated. The applied method of crystal structure determination consisted of three stages. In the first stage, the Le Bail method of X-ray pattern decomposition was used for the extraction of Al5O3N3 (15R) diffraction lines from a two-phase diffractogram. The space group and unit-cell dimensions from the isostructural SiAl4O2N4 SiAlON phase, producing the same X-ray pattern, were used as input data. Next, the direct structure determination in real space was applied for initial structural model derivation, which was followed by Rietveld refinement. The solved crystal structure of Al5O3N3 (15R), except the stacking sequence, proved to be closely related to the structure of Al7O3N5 (21R) polytype. The Al5O3N3 (15R) is trigonal with space group R-3m, unit-cell dimensions a0 = 3.0128 Å, c0 = 41.8544 Å, and volume V = 329.00 Å3. The model of Al5O3N3 (15R) polytype structure has positional disordering in one of three (6c) Al sites, which leads to stacking faults in six tetrahedral layers. Every third tetrahedron from LR3 and LR4, LR8 and LR9, LR13 and LR14 layers is rotated by 180°.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2017 

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References

Asaka, T., Kudo, T., Banno, H., Funahashi, S., Hirosaki, N., and Fukuda, K. (2013a). “Electron density distribution and crystal structure of 21R-AlON, Al7O3N5,” Powder Diffr., 28(3), 171177.CrossRefGoogle Scholar
Asaka, T., Banno, H., Funahashi, S., Hirosaki, N., and Fukuda, K. (2013b). “Electron density distribution and crystal structure of 27R-AlON, Al9O3N7,” J. Solid State Chem., 204, 2126.CrossRefGoogle Scholar
Crystal Impact GbR (2009). Endeavour Version 1.7 (Computer Software, Bonn, Germany).Google Scholar
ICDD (2015). PDF-4+ 2015 (Database), edited by Dr. Soorya Kabekkodu, International Centre for Diffraction Data, Newton Square, PA, USA.Google Scholar
Jack, K. H. (1976). “Sialons and related nitrogen ceramics,” J. Mater. Sci. 11, 11351158.CrossRefGoogle Scholar
Le Bail, A., Duroy, H., and Fourquet, J. L. (1988). “Ab-initio structure determination of LiSbWO6 by X-ray powder diffraction,” Mater. Res. Bull. 23, 447452.CrossRefGoogle Scholar
Lejus, A. M. (1962). “Preparation par reaction a l'etat solide et principales proprietes des oxynitrures d'aluminium,” Bull. Soc. Chim. Fr. 11-tz, 21232126.Google Scholar
McCauley, J. W. (2002). “Structure and properties of aluminum nitride and AlON ceramics”, Army Research Laboratory, Aberdeen Proving Ground, MD 210053069, (Report ARL-TR-2740).CrossRefGoogle Scholar
PANalytical, B. V. (2015). HighScorePlus, Version 4.1 (Computer Software, Almelo, The Netherlands).Google Scholar
Putz, H., Schon, J. C., and Jansen, M. (1999). “Combined method for ab initio structure solution from powder diffraction data,” J. Appl. Crystallogr. 32, 864870.CrossRefGoogle Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr. 32, 751767.CrossRefGoogle Scholar
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