PHASE TRANSITION OF CaFeO2.5 AT HIGH TEMPERATURE

T Labii, M Ceretti, A Boubertakh, W Paulus, S Hamamda

Résumé


The numerous studies conducted on the structure of CaFeO2.5 showed that the material undergoes a series of transformations based on temperature. The first one appears around 700 K and indicates the evolution of the phasemagnetic material to a paramagnetic phase. At about 970 K the structure of CaFeO2.5 changes from rhombohedral to centered structure. Finally, around 1180 K it undergoes the transition to a structure that has been described as incommensurate modulated structure. We have observed the behavior of the material beyond this temperature by dilatometry, DSC and TGA. The tests conducted on a single crystal CaFeO2.5 confirm the changes already observed.For the first time there was a dilatometric anomaly (confirmed by DSC and TGA) at 1310 K. This anomaly appears only in the crystallographic direction b which should probably be a  commensurate transformation of the material.

Mots-clés


Dilatometry; DSC; TGA; Dilatométrie

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Références


Taylor HFW. Cement chemistry, 2nded London: Thomas Telford.

Paulus W, Schober H, Eibl S, Johnson M, Berthier T, Hernadez O, Ceretti M, Plazanet M, Conder K, Lamberti C. Lattice dynamics to trigger low temperature oxygen mobility in solid oxide ion conductors. J Am Chem Soc. 2008;130:16080–5.

Bertaut EF, Blum P, Sagnie`res A. Structure du ferrite bicalciqueet de la broxnmellite. ActaCrystallogr. 1959;12:149–59. doi:10.1107/s0365110x59000433.

Smith D. Crystallographic changes with the substitution of aluminum for iron in dicalcium ferrite. Actacryst. 1962,1146-1152

Shaula AL, Pivaka YV, Waerenborghb JC, Gaczynˇskib P, Yaremchenkoa AA, Kharton VV. Ionic conductivity of brownmilleritetype calcium ferrite under oxidizing conditions. Solid State Ion. 2006;177:2923–30. doi:10.1016/j.ssi.2006.08.030.

Shin S, Yonemura M, and Ikawa H. Cristallographic properties of Ca2Fe2O5. Difference in crystallographic properties of browmillerite-like compounds, Ca2Fe2O5 and Sr2Fe2O5, at elevated temperatures. Bull of ChemSoc of Japan, 1979,52(3):947-948

Woodward PM, Cox DE, Moshopoulou E, Sleight AW, Morimoto S. Structural studies of charge disproportionation and magnetic order in CaFeO3. Phys Rev. 2000;2:844–55.

Takeda T, Yamaguchi Y, Tomiyoshi S, Fukase M, Sugimoto M, Watanabe H. Magnetic structure of Ca2Fe2O5. J Phys Soc Jpn.1968;24(3):446–52.

Berastegui P, Eriksson SG, Hull S. A neutron diffraction study of the temperature dependence of Ca2Fe2O5. Mater Res Bull.1999;34(2):303–14.

Redhammer GJ, Tippelt G, Roth G, Amhtauer G. Structural variations in the brownmillerite series Ca2(Fe2-xAlx)O5: single-crystal X-ray diffraction at 25 °C and high temperature X-ray powder diffraction (25 °C B T B 1,000 _C. Am Mineral. 2004; 89:405–20.

Lambert S, Leligny H, Grebile D, Pelloquin D, Raveau B. Modulated disribution of differently ordered tetrahedral chains in the brownmillerite structure. Chem Mater. 2002;14:1818–36.

Abakumov AM, Alekseeva AM, Pavlyuk BP, Lobanov MV, Antipov EV, Lebedev OI, Van Tendeloo G, Ignatchik OL, Ovtchenkov EA, Koksharov YA, Vasil’ev AN. Synthesis, crystal structure, and magnetic properties of a novel layered manganese oxide Sr2MnGaO5?d. J Solid State Chem. 2001;160:353–61. doi:10.1006/jssc.2001.9240.

Abakumov AM, Rozova MG, Antipov EV, Lebedev OI, Van Tendeloo G. Ordering of tetrahedral chains in the Sr2MnGaO5 brownmillerite. J Solid State Chem. 2003;174:319–28.

Abakumov AM, Kalyuzhnaya AS, Rozova MG, Antipov EV, Hadermann J, VanTendeloo G. compositionally induced phase transition in the Ca2MnGa1-xAlxO5 solid solutions. Solid State Sci. 2005;7:801–11.

Küger H, Kahlenberg V. Incommensurately modulated ordering of tetrahedral chains in Ca2Fe2O5 at elevated temperatures. ActaCrystallogr. 2005;B61:656–62. doi:10.1107/s0108768105026480.

Lazic B, Krüger H, Kahlenberg V, Konzett J, Kaind R. The incommensurate structure of Ca2Al2O5 at high temperature-Dilatometric study of CaFeO2.5 single crystal structure investigation and Raman spectroscopy.ActaCrystallogr. 2008;B64:417–25.

doi:10.1107/s0108768108016029.

Corliss LM, Hastings JM, Kunnmann W, Banks E. Magnetic structures and exchange interactions in the systems CaCrxFe2xO4 and Ca2CrxFe2xO5. Acta Crystallogr. 1966;21:A95.

T. Labii, M. Ceretti, W. Paulus, S. Hamamda, spo2010 Kyiv, (2010) 89.

T. Labii, M. Ceretti, W. Paulus, S. Hamamda, SF2M (2011) St. Etienne

Woermann E, Eysel W, Hahn T. Polymorphism and solid solution of the ferrite phase. In: Proceedings of the 5th international symposium on the chemistry of cement, Tokyo: Supplementary Paper I-54; 1968. pp. 54–60.


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