Skip to main content Accessibility help

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

  • M. C. Gallardo (a1), F. J. Romero (a1), S. A. Hayward (a1), E. K. H. Salje (a2) and J. del Cerro (a1)...


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 Q 6. 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.


Corresponding author



Hide All
Chrosch, J. and Salje, E.K.H. (1998) Near-surface domain structures in uniaxially stressed SrTiO3 . J. Phys.: Condens. Matt., 10, 2817–27.
del Cerro, J. (1987) New measurement method of thermal properties by means of flux calorimetry. J. Phys. E, 20, 609–11.
del Cerro, J., Martín, J.-M. and Ramos, S. (1996) Specific heat measurements under non-equilibrium conditions. J. Therm. Anal., 47, 1691–700.
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, 8997.
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.
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.
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.
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.
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.
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.
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.
Jiménez, J., Rojas, E. and Zamora, M. (1984) Design and construction of precision heat fluxmeters. J. Appl. Phys., 56, 3353–6.
Le Guillou, J.C. and Zinn-Justin, J. (1980) Critical exponents from field theory. Phys. Rev. B, 21, 3976–98.
Lines, M.E. and Glass, A.M. (1977) Principles and Applications of Ferroel ectric s and Related Materials, Clarendon Press, Oxford.
Minkiewicz, V.J. and Shirane, G. (1969) Soft phonon mode in KMnF3 . J. Phys. Soc. Japan, 26, 674–80.
Müller, K.A., Berlinger, W. and Slonczewski, J.C. (1970) Order parameter and phase transitions of stressed SrTiO3 . Phys. Rev. Lett., 25, 734–7.
Navrotsky, A. and Weidner, D. (editors) (1989) Perovskite: a Structure of Great Interest to Geophysics and Materials Science. American Geophysical Union, Washington D.C..
Redfern, S.A.T. (1992) The effect of Al/Si disorder on the I1̄–P1̄ co-elastic phase transition in Ca-rich plagioclase. Phys. Chem. Min., 19, 246–54.
Romero, F.J. (2000) Estudio termodinámico de cristales tipo perovskita en las cercanõ´as del punto tricrítico. Doctoral Thesis, Univ. Seville, Spain.
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.
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.
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.
Salje, E.K.H. (1990) Phase Transitions in Ferroelastic and Co-elastic Crystals. Cambridge University Press, Cambridge, UK.
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.
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.
Shirane, G. and Yamada, Y. (1969) Lattice dynamical study of the 110 K phase transition in SrTiO3 . Phys. Rev. 177, 858–63.
Stokka, S. and Fossheim, K. (1982) Specific heat and phase diagrams for uniaxially stressed KMnF3 . J. Phys. C., 15, 1161–76.
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.



Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed