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A temperature-dependent powder diffraction study of chromium lanthanum nitrate, LaCr(NO3)6·12H2O

Published online by Cambridge University Press:  10 January 2013

A.-E. Gobichon
Affiliation:
Laboratoire de Chimie du Solide et Inorganique Moléculaire (U.M.R. C.N.R.S. 6511), Université de Rennes 1, Avenue du Général Leclerc, 35042 Rennes cedex, France
J.-P. Auffrédic
Affiliation:
Laboratoire de Chimie du Solide et Inorganique Moléculaire (U.M.R. C.N.R.S. 6511), Université de Rennes 1, Avenue du Général Leclerc, 35042 Rennes cedex, France
D. Louër
Affiliation:
Laboratoire de Chimie du Solide et Inorganique Moléculaire (U.M.R. C.N.R.S. 6511), Université de Rennes 1, Avenue du Général Leclerc, 35042 Rennes cedex, France

Abstract

The new phase LaCr(NO3)6·12H2O was synthesized from a nitric acid solution. The symmetry is trigonal with the parameters a=10.9564(4) Å and c=16.835(1) Å [V=1750.2(2) Å3, space group R-3]. The thermal decomposition, studied by temperature-dependent X-ray powder diffraction and thermogravimetry, gave successively the cubic phase LaCr(NO3)6·6H2O [a=12.301(1) Å, space group P213] and the chromate(V) LaCrO4. The reduction of LaCrO4 to LaCrO3 occurred at a temperature depending on the oxygen pressure in the reaction atmosphere.

Type
Technical Articles
Copyright
Copyright © Cambridge University Press 2000

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References

Boultif, A., and Louër, D. (1991). “Indexing of powder diffraction patterns for low-symmetry lattices by the successive dichotomy method,” J. Appl. Crystallogr. 24, 987993.CrossRefGoogle Scholar
Bueno, I., Parada, C., Saez Puche, R., and Baran, E. J. (1995). “Synthesis, thermal decomposition, magnetic properties and vibrational study of the series Ln(OH)CrO 4 (Ln=Y, Dy-Lu),” J. Alloys Compd. 225, 237241.CrossRefGoogle Scholar
Devi, P. S., and Rao, M. S. (1989). “Rare-earth chromium citrates as precursors for rare-earth chromites: lanthanum biscitrato chromium(III) dihydrate, La[Cr(C 6H 5O 7)2].2H 2O,Thermochim. Acta 15, 181191.CrossRefGoogle Scholar
Devi, P. S., and Rao, M. S. (1993). “Low temperature preparation and characterization of phase-pure lanthanide chromate V by the citrate gel,” Mater. Lett. 16, 1421.CrossRefGoogle Scholar
Furusaki, A. (1997). “Synthesis and properties of perovskite-type LaCrO 3,Zairyo To Kankyo 46, 126133.CrossRefGoogle Scholar
Gobichon, A.-E., Auffrédic, J.-P., and Louër, D. (1998). “Structure and thermal behaviour of lanthanum aluminium nitrates,” J. Alloys Compd. 275–277, 130136.CrossRefGoogle Scholar
Guillou, N., Auffrédic, J. P., and Louër, D. (1995). “An unexpected double valence change for cerium during the thermal decomposition of CeK 2(NO 3)6,J. Solid State Chem. 115, 295298.CrossRefGoogle Scholar
Leskelä, M., and Niinistö, L. (1986). “Inorganic complex compounds I,” in “Handbook of the physics and chemistry of rare earths,” edited by K. A. Gschneidner Jr. and L. Eyring (Elsevier, Amsterdam), Vol. 8, Chap. 56, pp. 203–334.Google Scholar
Meadowcroft, D. B. (1970). “Low-cost oxygen electrode material,” Nature (London) 226, 847848.CrossRefGoogle ScholarPubMed
Mighell, A. D., Hubbard, C. R., and Stalick, J. K. (1981). “A FORTRAN Program for Crystallographic Data Evaluation,” Nat. Bur. Stand. (U.S.) Tech. Note 1141. [NBS *AIDS83 is an expanded version of NBS *AIDS80].Google Scholar
Plévert, J., Auffrédic, J.-P., Louër, M., and Louër, D. (1989). “Time-resolved study by X-ray powder diffraction with position-sensitive detector: rate of the β-Cs 2CdI 4 transformation and the effect of preferred orientation,” J. Mater. Sci. 24, 19131918.CrossRefGoogle Scholar
Sakamoto, M., Matsuki, K., Ohsumi, R., Nakayama, Y., Sadaoka, Y., Nakayama, S., Matsumoto, N., and Okawa, H. (1992). “Preparation and properties of perovskite-type oxides from three-dimensional heterometal assemblies, {LnCr(ox)3.10H 2O}x (Ln=La, Pr, or Nd),” J. Ceram. Soc. Jpn. 100, 12111215.CrossRefGoogle Scholar
Teraoka, Y., Zhang, H. M., Furukawa, S., and Yamazoe, N. (1985). “Oxygen permeation through perovskite-type oxides,” Chem. Lett., 17431746.CrossRefGoogle Scholar
Tseung, A. C. C., and Bevan, H. L. (1973). “A reversible oxygen electrode,” J. Electroanal. Chem. 45, 429438.CrossRefGoogle Scholar