Abstract
The data on the phase transitions in the series of rare earth sesquioxides are considered in terms of the thermodynamic theory of morphotropism. It is shown that the scheme of polymorphism and morphotropism suggested by V.V. Glushkova is the most adequate. The derivatographic dehydration of lanthanum and neodymium oxide hydrates is performed. The transition of the cubic C modification into the hexagonal A modification of neodymium oxide is accompanied by the removal of volatile impurities and, thus, is not a polymorphic transition proper.
Similar content being viewed by others
References
J. Warshaw and R. Roy, J. Phys. Chem. 65, 2048 (1961).
G. Brauer and R. Muller, Z. Anorg. Allg. Chem. 321(5–6), 234 (1963).
M. Foex and J.-P. Traverse, C. R. Seances Acad. Sci. 262, 636 (1966).
V. B. Glushkova, Polymorphism of Rare-Earth Oxides (Nauka, Leningrad, 1967).
V. S. Rudenko and A. G. Bogdanov, Izv. Akad. Nauk SSSR, Neorg. Mater. 6(12), 2158 (1970).
J.-P. Traverse, Contribution au developpement de méthodes d’experimentation a temperature elevée. Application a l’étude du polymorphisme des sesquioxydes de terres rares et des changements de phases dans les systems zircone-chaux et zircone-oxyde de strontium, Thése (L’Univérsite Scientifique et Medicale de Grenoble, Grenoble, 1971).
L. M. Lopato, F. V. Shevchenko, A. E. Kushchevskii, and S. G. Tresvyatskii, Izv. Akad. Nauk SSSR, Neorg. Mater. 10(8), 1481 (1974).
P. Duran, Bull. Soc. Fr. Ceram., No. 102, 47 (1974).
J. Coutures, A. Rouanet, R. Verges, and M. Foex, J. Solid State Chem. 17(1/2), 171 (1976).
O. Greis, J. Solid State Chem. 34(1), 39 (1980).
C. Boulesteix, Handbook on the Physics and Chemistry of Rare Earth, Ed. by K. A. Gschneidner and L. Eyring (North-Holland, Amsterdam, 1982), Chap. 44, p. 321.
B. I. Pokrovskii and F. M. Spiridonov, in Compounds of Rare-Earth Elements. Systems with Oxides of Elements from Groups I–III, Ed. by I. V. Tananaev (Nauka, Moscow, 1983), p. 17.
F. Weigel and U. Scherer, Radiochim. Acta 4, 197 (1965).
P. P. Fedorov, Kristallografiya 40, 308 (1995) [Crystallogr. Rep. 40, 278 (1995)].
P. P. Fedorov and B. P. Sobolev, Kristallografiya 40, 315 (1995).
V. P. Klevtsov and L. P. Sheina, Izv. Akad. Nauk SSSR, Neorg. Mater. 1(12), 2219 (1965).
B. N. Rybakov, A. F. Moskvicheva, and G. D. Beregovaya, Zh. Neorg. Khim. 14(11), 2904 (1969).
B. G. Hyde, Acta Crystallogr., Sect. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr. A27(6), 617 (1971).
R. D. Shannon, Acta Crystallogr., Sect. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr. A32(5), 751 (1976).
P. P. Fedorov, L. V. Medvedeva, and B. P. Sobolev, Zh. Fiz. Khim. 67(5), 1073 (1993).
P. P. Fedorov, P. I. Fedorov, and B. P. Sobolev, Zh. Neorg. Khim. 18(12), 3319 (1973).
Author information
Authors and Affiliations
Additional information
__________
Translated from Kristallografiya, Vol. 47, No. 2, 2002, pp. 316–321.
Original Russian Text Copyright © 2002 by Fedorov, Nazarkin, Zakalyukin.
Rights and permissions
About this article
Cite this article
Fedorov, P.P., Nazarkin, M.V. & Zakalyukin, R.M. On polymorphism and morphotropism of rare earth sesquioxides. Crystallogr. Rep. 47, 281–286 (2002). https://doi.org/10.1134/1.1466504
Received:
Issue Date:
DOI: https://doi.org/10.1134/1.1466504