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Phase transitions in perovskites near the tricritical point: an experimental study of KMn1–xCaxF3 and SrTiO3

Published online by Cambridge University Press:  05 July 2018

M. C. Gallardo ,
F. J. Romero ,
S. A. Hayward ,
E. K. H. Salje  and
J. del Cerro
M. C. Gallardo*
Affiliation:
Departamento de Física de la Materia Condensada, Universidad de Sevilla, PO Box 1065, E-41080 Sevilla, Spain
F. J. Romero
Affiliation:
Departamento de Física de la Materia Condensada, Universidad de Sevilla, PO Box 1065, E-41080 Sevilla, Spain
S. A. Hayward
Affiliation:
Departamento de Física de la Materia Condensada, Universidad de Sevilla, PO Box 1065, E-41080 Sevilla, Spain
E. K. H. Salje
Affiliation:
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
J. del Cerro
Affiliation:
Departamento de Física de la Materia Condensada, Universidad de Sevilla, PO Box 1065, E-41080 Sevilla, Spain
*
*E-mail: mcgallar@cica.es
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Abstract

We present experimental data for the Pm3m-I4/mcm phase transitions in the perovskite crystals KMn1-xCaxF3 and SrTiO3. Comparison of calorimetric data (latent heat and specific heat) with order parameter data (measured with X-ray rocking methods) indicates that these transitions follow mean-field behaviour, and may be described using Landau potentials where the free energy expansion includes terms up to Q6. This potential is characteristic of transitions close to the tricritical point. Comparison of the behaviour of SrTiO3 and KMnF3 indicates that KMnF3 is closer to the tricritical point; a small amount of substitution of Ca for Mn causes the transition to cross the tricritical point from first order to second order behaviour.

Keywords

phase transitionperovskitetricritical pointLandau theory
Type
Research Article
Information
Mineralogical Magazine , Volume 64 , Issue 6 , December 2000 , pp. 971 - 982
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2000

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References

Chrosch, J. and Salje, E.K.H. (1998) Near-surface domain structures in uniaxially stressed SrTiO3 . J. Phys.: Condens. Matt., 10, 2817–27.Google Scholar
del Cerro, J. (1987) New measurement method of thermal properties by means of flux calorimetry. J. Phys. E, 20, 609–11.CrossRefGoogle Scholar
del Cerro, J., Martín, J.-M. and Ramos, S. (1996) Specific heat measurements under non-equilibrium conditions. J. Therm. Anal., 47, 1691–700.CrossRefGoogle Scholar
del Cerro, J., Romero, F.J., Gallardo, M.C., Hayward, S.A. and Jiménez, J. (2000) Latent heat measurement near a tricritical point: a study of the KMnF3 ferroelastic crystal. Thermochim. Acta, 343, 89–97.CrossRefGoogle Scholar
Gallardo, M.C., Jiménez, J. and del Cerro, J. (1995) Experimental device for measuring the influence of uniaxial stress on specific heat: Application to the strontium titanate ferroelastic crystal. Rev. Sci. Instrum., 66, 5288–91.CrossRefGoogle Scholar
Gallardo, M.C., Jiménez, J., del Cerro, J. and Salje, E.K.H. (1996) The structural phase transition in SrTiO3 under uniaxial stress in the [110] direction: a calorimetric study. J. Phys.: Condens. Matt., 8, 83–9.Google Scholar
Gallardo, M.C., Jiménez, J., Koralewski, M. and del Cerro, J. (1997) First order transitions by conduction calorimetry: Application to deuterated potassium dihydrogen phosphate. J. Appl. Phys., 81, 2584–9.CrossRefGoogle Scholar
Gibaud, A., Shapiro, S.M., Nouet, J. and You, H. (1991) Phase diagram of KMnF1–xCaxF3 (x<0.05) determined by high resolution X-ray scattering. Phys. Rev. B, 44, 2437 43.CrossRefGoogle ScholarPubMed
Ginzburg, V.L., Levanyuk, A.P. and Sobyanin, A.A. (1987) Comments on the region of applicability of the Landau theory of structural phase transitions. Ferroelectrics, 73, 171–82.CrossRefGoogle Scholar
Hayward, S.A. and Salje, E.K.H. (1999) Cubic-tetragonal phase transition in SrTiO3 revisited: Landau theory and transition mechanism. Phase Transitions, 68, 501–22.CrossRefGoogle Scholar
Hayward, S.A., Romero, F.J., Gallardo, M.C., del Cerro, J., Gibaud, A. and Salje, E.K.H. (2000) Cubictetragonal phase transition in KMnF3: excess entropy and spontaneous strain. J. Phys.: Condens. Matt., 12, 1133–42.Google Scholar
Jiménez, J., Rojas, E. and Zamora, M. (1984) Design and construction of precision heat fluxmeters. J. Appl. Phys., 56, 3353–6.CrossRefGoogle Scholar
Le Guillou, J.C. and Zinn-Justin, J. (1980) Critical exponents from field theory. Phys. Rev. B, 21, 3976–98.CrossRefGoogle Scholar
Lines, M.E. and Glass, A.M. (1977) Principles and Applications of Ferroel ectric s and Related Materials, Clarendon Press, Oxford.Google Scholar
Minkiewicz, V.J. and Shirane, G. (1969) Soft phonon mode in KMnF3 . J. Phys. Soc. Japan, 26, 674–80.CrossRefGoogle Scholar
Müller, K.A., Berlinger, W. and Slonczewski, J.C. (1970) Order parameter and phase transitions of stressed SrTiO3 . Phys. Rev. Lett., 25, 734–7.CrossRefGoogle Scholar
Navrotsky, A. and Weidner, D. (editors) (1989) Perovskite: a Structure of Great Interest to Geophysics and Materials Science. American Geophysical Union, Washington D.C..CrossRefGoogle Scholar
Redfern, S.A.T. (1992) The effect of Al/Si disorder on the I –P co-elastic phase transition in Ca-rich plagioclase. Phys. Chem. Min., 19, 246–54.CrossRefGoogle Scholar
Romero, F.J. (2000) Estudio termodinámico de cristales tipo perovskita en las cercanõ´as del punto tricrítico. Doctoral Thesis, Univ. Seville, Spain.Google Scholar
Romero, F.J., Gallardo, M.C., Jiménez, J. and del Cerro, J. (2000 a) Discrimination of the transition order extremely close to tricritical point. Thermochim. Acta, submitted.Google Scholar
Romero, F.J., Gallardo, M.C., Hayward, S.A. and del Cerro, J. (2000 b) Landau Theory in KMn1–xCaxF3 ferroelastic crystal near the tricritical point: Calorimetric and order parameter study. J. Phys.: Condens. Matt., submitted.Google Scholar
Sakashita, H., Ohama, N. and Okazaki, A. (1981) Measurement of the lattice constant of KMnF3 around the 186 K phase transition: Determination of the critical exponent. J. Phys. Soc. Japan, 50, 4013–21.CrossRefGoogle Scholar
Salje, E.K.H. (1990) Phase Transitions in Ferroelastic and Co-elastic Crystals. Cambridge University Press, Cambridge, UK.Google Scholar
Salje, E.K.H., Gallardo, M.C., Jiménez, J., Romero, F.J. and del Cerro, J. (1998) The cubic-tetragonal phase transition in strontium titanate: excess specific heat measurements and evidence for a near-tricritical, mean field type transition mechanism. J. Phys.: Condens. Matt., 10, 5535–43.Google Scholar
Sato, M., Soejima, Y., Ohama, N., Okazaki, A., Schel, H.J. and Müller, K.A. (1985) The lattice constant vs. temperature relation around the 105 K transition of a flux-grown SrTiO3 crystal. Phase Transitions, 5, 207–18.CrossRefGoogle Scholar
Shirane, G. and Yamada, Y. (1969) Lattice dynamical study of the 110 K phase transition in SrTiO3 . Phys. Rev. 177, 858–63.CrossRefGoogle Scholar
Stokka, S. and Fossheim, K. (1982) Specific heat and phase diagrams for uniaxially stressed KMnF3 . J. Phys. C., 15, 1161–76.CrossRefGoogle Scholar
Wruck, B., Salje, E.K.H., Zhang, M., Abraham, T. and Bismayer, U. (1994) On the thickness of ferroelastic twin walls in lead phosphate Pb3(PO4)2: an X-ray diffraction study. Phase Transitions, 48, 135–48.CrossRefGoogle Scholar