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Electron density distribution and crystal structure of Ca1-x/2AlSi(N3-xOx):Eu2+ (x ∼ 0.11)

Published online by Cambridge University Press:  06 March 2012

Daisuke Urushihara ,
Toru Asaka ,
Takashi Takeda ,
Naoto Hirosaki  and
Koichiro Fukuda
Daisuke Urushihara
Affiliation:
Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Toru Asaka
Affiliation:
Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Takashi Takeda
Affiliation:
Nano Ceramics Center, National Institute for Materials Science (NIMS), Ibaraki 305-0044, Japan
Naoto Hirosaki
Affiliation:
Nano Ceramics Center, National Institute for Materials Science (NIMS), Ibaraki 305-0044, Japan
Koichiro Fukuda*
Affiliation:
Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]
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Abstract

Crystal structure of Ca1-x/2AlSi(N3-xOx):Eu2+ (x ∼ 0.11) has been characterized using an X-ray powder diffractometer and a transmission electron microscope equipped with an energy dispersive X-ray analyzer (EDX) and an electron energy loss spectrometer (EELS). The title compound is orthorhombic with space group Cmc21, Z = 4, unit-cell dimensions a = 0.979780(7) nm, b = 0.565197(4) nm, c = 0.506356(3) nm, and V = 0.280404(3) nm3. The atom ratio Al:Si was determined to be 1:1 by EDX, and the presence of O atoms in the crystal structure was confirmed by EELS. The x-value and the atomic coordinates of the final structural model were determined by the Rietveld method. The maximum-entropy methods-based pattern fitting (MPF) method was used to confirm the validity of the structural model, in which conventional structure bias caused by assuming intensity partitioning was minimized. The reliability indices calculated from MPF are Rwp = 9.18%, S = 1.17, Rp = 6.77%, RB = 1.91%, and RF = 0.86%. Atomic arrangements of the final structural model are in an excellent agreement with the three dimensional electron-density distributions determined by MPF.

Keywords

calcium aluminum silicon oxynitrideX-ray powder diffractionRietveld methodmaximum-entropy methodelectron density distributions
Type
Technical Articles
Information
Powder Diffraction , Volume 26 , Supplement S1 , December 2011 , pp. S38 - S43
Copyright
Copyright © Cambridge University Press 2011

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References

Brindley, G. W. (1949). “Quantitative X-ray analysis of crystalline substances or phases in their mixtures,” Bull. Soc. Chim. Fr. D59–63.Google Scholar
NIST-JANAF Thermochemical Tables 2 Volume Set (Journal of Physical and Chemical Reference Data Monographs), edited by Chase, M. W. Jr., (1998), No. 9, 4th ed. (American Chemical Society and American Institute of Physics, Woodbury, NY).Google Scholar
Gelato, L. M. and Parthé, E. (1987). “STRUCTURE TIDY—A computer program to standardize crystal structure data,” J. Appl. Crystallogr. 20, 139–143.10.1107/S0021889887086965CrossRefGoogle Scholar
Izumi, F. (2004). “Beyond the ability of Rietveld analysis: MEM-based pattern fitting,” Solid State Ionics 172, 1–6.10.1016/j.ssi.2004.04.023CrossRefGoogle Scholar
Izumi, F. and Dilanian, R. A. (2002). “Structure refinement based on the maximum-entropy method from powder diffraction data,” Recent Res. Dev. Phys. 3, Pt. II, 699–726.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, 59–64.10.4028/www.scientific.net/MSF.378-381.59CrossRefGoogle Scholar
Izumi, F. and Momma, K. (2007). “Three-dimensional visualization in powder diffraction,” Solid State Phenom. 130, 15–20.10.4028/www.scientific.net/SSP.130.15CrossRefGoogle Scholar
Kulikov, I. S. (1986). Thermodynamics of Oxides (Metallurgiya, Moscow, U.S.S.R).Google Scholar
Li, J., Watanabe, T., Wada, H., Setoyama, T., and Yoshimura, M. (2007). “Low-temperature crystallization of Eu-doped red-emitting CaAlSiN3 from alloy-derived ammonometallates,” Chem. Mater. 19, 3592–3594.10.1021/cm070994tCrossRefGoogle Scholar
Li, J., Watanabe, T., Sakamoto, N., Wada, H., Setoyama, T., and Yoshimura, M. (2008). “Synthesis of a multinary nitride, Eu-doped CaAlSiN3, from alloy at low temperatures,” Chem. Mater. 20, 2095–2105.10.1021/cm071612mCrossRefGoogle Scholar
McCarthy, G. J. (1974). “Oxygen-fugacity-temperature diagram for the Eu-O system”, J. Am. Ceram. Soc. 57, 502.10.1111/j.1151-2916.1974.tb11406.xCrossRefGoogle Scholar
Momma, K. and Izumi, F. (2008). “VESTA: A three-dimensional visualization system for electronic and structural analysis,” J. Appl. Crystallogr. 41, 653–658.10.1107/S0021889808012016CrossRefGoogle Scholar
Parthé, E. and Gelato, L. M. (1984). “The standardization of inorganic crystal-structure data,” Acta Crystallogr., Sec. A: Sect. A: Found. Crystallogr. 40, 169–183.10.1107/S0108767384000416CrossRefGoogle Scholar
Piao, X., Machida, K., Horikawa, T., Hanzawa, H., Shimomura, Y., and Kijima, N. (2007). “Preparation of CaAlSiN3:Eu2+ phosphors by the self-propagating high-temperature synthesis and their luminescent properties,” Chem. Mater. 19, 4592–4599.10.1021/cm070623cCrossRefGoogle Scholar
Rietveld, H. M. (1967). “Line profiles of neutron powder-diffraction peaks for structure refinement,” Acta Crystallogr. 22, 151–152.10.1107/S0365110X67000234CrossRefGoogle Scholar
Schulz, H. and Thiemann, K. H. (1977). “Crystal structure refinement of AlN and GaN,” Solid State Commun. 23, 815–819.10.1016/0038-1098(77)90959-0CrossRefGoogle Scholar
Sjöberg, J., Helgesson, G., and Idrestedt, I. (1991). “Refinement of the structure of Si2N2O,” Acta Crystallogr., Sect. C: Cryst. Struct. Commun. 47, 2438–2441.10.1107/S0108270191006236CrossRefGoogle 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, 71–86.10.1524/zkri.216.2.71.20335CrossRefGoogle Scholar
Toraya, H. (1990). “Array-type universal profile function for powder pattern fitting,” J. Appl. Crystallogr. 23, 485–491.10.1107/S002188989000704XCrossRefGoogle Scholar
Uheda, K., Hirosaki, N., Yamamoto, Y., Naito, A., Nakajima, T., and Yamamoto, H. (2006a). “Luminescence properties of a red phosphor, CaAlSiN3:Eu2+, for white light-emitting diodes,” Electrochem. Solid-State Lett. 9, H22–H25.10.1149/1.2173192CrossRefGoogle Scholar
Uheda, K., Hirosaki, N., and Yamamoto, H. (2006b). “Host lattice materials in the system Ca3N2-AlN-Si3N4 for white light emitting diode,” Phys. Status Solidi A 203, 2712–2717.10.1002/pssa.200669576CrossRefGoogle Scholar
Uheda, K., Yamamoto, H., Yamane, H., Inami, W., Tsuda, K., Yamamoto, Y., and Hirosaki, N. (2009). “An analysis of crystal structure of Ca-deficient oxonitridoaluminosilicate, Ca0.88Al0.91Si1.09N2.85O0.15,” J. Ceram. Soc. Jpn. 117, 94–98.10.2109/jcersj2.117.94CrossRefGoogle Scholar
Xie, R.-J. and Hirosaki, N. (2007). “Silicon-based oxynitride and nitride phosphors for white LEDs—A review,” Sci. Technol. Adv. Mater. 8, 588–600.10.1016/j.stam.2007.08.005CrossRefGoogle Scholar
Young, R. A. (1993). “Introduction to the Rietveld Method,” in The Rietveld Method, edited by Young, R. A. (Oxford University Press, Oxford, U.K.) pp. 1–38.CrossRefGoogle Scholar