Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-05T19:29:15.494Z Has data issue: false hasContentIssue false

Electron-density distribution and disordered crystal structure of 12H-SiAlON, SiAl5O2N5

Published online by Cambridge University Press:  10 June 2014

Hiroki Banno
Affiliation:
Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Takaaki Hanai
Affiliation:
Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Toru Asaka
Affiliation:
Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Koji Kimoto
Affiliation:
Advanced Key Technologies Division, National Institute for Materials Science, Tsukuba 305-0044, Japan
Hiromi Nakano
Affiliation:
Cooperative Research Facility Center, Toyohashi University of Technology, Toyohashi 441-8580, Japan
Koichiro Fukuda*
Affiliation:
Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
*
a) Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

The crystal structure of SiAl5O2N5 was characterized by laboratory X-ray powder diffraction (CuKα1). The title compound is hexagonal with space group P63/mmc (Z = 2). The unit-cell dimensions are a = 0.303153(3) nm, c = 3.28153(3) nm, and V = 0.261178(5)  nm3. The initial structural model was successfully derived by the direct methods and further refined by the Rietveld method. The final structural model showed the positional disordering of two of the four (Si,Al) sites. The maximum-entropy method-based pattern fitting (MPF) method was used to confirm the validity of the split-atom model, in which conventional structure bias caused by assuming intensity partitioning was minimized. The reliability indices calculated from the MPF were R wp = 5.00%, S (=R wp/R e) = 1.25, R p = 3.76%, R B = 1.26%, and R F  = 0.90%. The disordered crystal structure was successfully described by overlapping four types of domains with ordered atom arrangements. The distribution of atomic positions in each of the domains can be achieved in the space group P63 mc. Two of the four types of domains are related by a pseudo-symmetry inversion, and the two remaining domains also have each other the inversion pseudo-symmetry.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Altomare, A., Camalli, M., Cuocci, C., Giacovazzo, C., Moliterni, A. G. G., and Rizzi, R. (2009). “EXPO2009: structure solution by powder data in direct and reciprocal space,” J. Appl. Crystallogr. 42, 11971202.CrossRefGoogle Scholar
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, 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
Bando, Y., Mitomo, M., Kitami, Y., and Izumi, F. (1986). “Structural and composition analysis of silicon aluminium oxynitride polytypes by combined use of structure imaging and microanalysis,” J. Microsc. 142, 235246.Google Scholar
Banno, H., Hanai, T., Asaka, T., Kimoto, K., and Fukuda, K. (2014). “Electron density distribution and disordered crystal structure of 15R-SiAlON, SiAl4O2N4 ,” J. Solid State Chem. 211, 124129.Google Scholar
Bartram, S. F. and Slack, G. A. (1979). “Al10N8O3 and Al9N7O3, two new repeated-layer structures in the AlN–Al2O3 system,” Acta Crystallogr. B35, 22812283.Google Scholar
Gelato, L. M. and Parthé, E. (1987). “STRUCTURE TIDY – a computer program to standardize crystal structure data,” J. Appl. Crystallogr. 20, 139143.Google Scholar
Giacovazzo, C. (1992). Direct Phasing in Crystallography: Fundamentals and Applications (Oxford University Press, Oxford).Google Scholar
Inuzuka, H., Kaga, M., Urushihara, D., Nakano, H., Asaka, T., and Fukuda, K. (2010). “Synthesis and structural characterization of a new aluminum oxycarbonitride, Al5(O, C, N)4 ,” J. Solid State Chem. 183, 25702575.Google Scholar
Iwata, T., Kaga, M., Nakano, H., and Fukuda, K. (2009). “First discovery and structural characterization of a new compound in Al–Si–O–C system,” J. Solid State Chem. 182, 22522260.Google Scholar
Izumi, F. (2004). “Beyond the ability of Rietveld analysis: MEM-based pattern fitting,” Solid State Ion. 172, 16.CrossRefGoogle Scholar
Izumi, F. and Momma, K. (2007). “Three-dimensional visualization in powder diffraction,” Solid State Phenom. 130, 1520.Google Scholar
Izumi, F. and Momma, K. (2011). “Three-dimensional visualization of electron- and nuclear-density distributions in inorganic materials by MEM-based technology,” IOP Conf. Ser. Mater. Sci. Eng. 18, 022001.Google Scholar
Izumi, F., Kumazawa, S., Ikeda, T., Hu, W.-Z., Yamamoto, A., and Oikawa, K. (2001). “MEM-based structure-refinement system REMEDY and its applications,” Mater. Sci. Forum 378–381, 5964.CrossRefGoogle Scholar
Jack, K. H. (1976). “Sialons and related nitrogen ceramics,” J. Mater. Sci. 11, 11351158.Google Scholar
Kaga, M., Iwata, T., Nakano, H., and Fukuda, K. (2010a). “Synthesis and structural characterization of Al4SiC4-homeotypic aluminum silicon oxycarbide, [Al4.4Si0.6][O1.0C2.0]C,” J. Solid State Chem. 183, 636642.Google Scholar
Kaga, M., Urushihara, D., Iwata, T., Sugiura, K., Nakano, H., and Fukuda, K. (2010b). “Synthesis and structural characterization of Al4Si2C5-homeotypic aluminum silicon oxycarbide, (Al6− x Si x )(O y C5− y ) (x ~ 0.8 and y ~ 1.6),” J. Solid State Chem. 183, 21832189.Google 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.Google Scholar
Momma, K. and Izumi, F. (2011). “VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data,” J. Appl. Crystallogr. 44, 12721276.Google Scholar
Parthé, E. (1964). Crystal Chemistry of Tetrahedral Structures (Gordon and Breach, New York).Google Scholar
Parthé, E. and Gelato, L. M. (1984). “The standardization of inorganic crystal-structure data,” Acta Crystallogr. A10, 169183.Google Scholar
Rietveld, H. M. (1967). “Line profiles of neutron powder-diffraction peaks for structure refinement,” Acta Crystallogr. 22, 151152.Google Scholar
Sakai, T. (1978). “Hot-pressing of the AlN-Al2O3 system,” J. Ceram. Soc. Jpn (Yogyo-Kyokai-shi) 86, 125130.Google Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A32, 751767.Google Scholar
Tabary, P. and Servant, C. (1998). “Thermodynamic reassessment of the AlN–Al2O3 system,” Calphad 22, 179201.Google Scholar
Tabary, P. and Servant, C. (1999a). “Crystalline and microstructure study of the AlN–Al2O3 section in the Al–N–O system. I. Polytypes and γ-AlON spinel phase,” J. Appl. Crystallogr. 32, 241252.Google Scholar
Tabary, P. and Servant, C. (1999b). “Crystalline and microstructure study of the AlN–Al2O3 section in the Al–N–O system. II. φ′ - and δ-AlON spinel phases,” J. Appl. Crystallogr. 32, 253272.Google Scholar
Takata, M., Nishibori, E., and Sakata, M. (2001). “Charge density studies utilizing powder diffraction and MEM. Exploring of high Tc superconductors, C60 superconductors and manganites,” Z. Kristallogr. 216, 7186.Google Scholar
Toraya, H. (1990). “Array-type universal profile function for powder pattern fitting,” J. Appl. Crystallogr. 23, 485491.Google Scholar
Urushihara, D., Kaga, M., Asaka, T., Nakano, H., and Fukuda, K. (2011). “Synthesis and structural characterization of Al7C3N3-homeotypic aluminum silicon oxycarbonitride, (Al7− x Si x ) (O y C z N6− y z ) (x ~ 1.2, y ~ 1.0 and z ~ 3.5),” J. Solid State Chem. 184, 22782284.Google Scholar
Young, R. A. (1993). “Introduction to the Rietveld method” in The Rietveld Method, edited by Young, R. A. (Oxford University Press, Oxford), pp. 138.Google Scholar