Calorimetric and Thermodynamic Studies of Complex Ferrites

Abstract:

By method of dynamic calorimetry, in the temperature range between 298,15 and 673 K, isobaric heat capacity of polycrystalline ferrites Bі₂СаFe₄O₁₀, BіMgFe₂O_5.5, Bі₂MgFe₄O₁₀ was experimentally studied. Mathematical processing of experimental data made it possible to derive polynomial equation of temperature dependence of ferrites heat capacity for respective temperature ranges, in dependencies C⁰_p~f (T) of ferrite Bі₂СаFe₄O₁₀ a jump was detected in heat capacity at 625K associated with phase transitions of type II. The values of the thermodynamic functions C⁰_p(Т), H⁰(T) – Н⁰(298,15), C⁰(T), F^hh(Т) have been calculated. Standard values of thermodynamic functions were determined using the method of ion increments. The results obtained broaden thermodynamic data bank for complex inorganic crystalline compounds.

• Periodical: Applied Mechanics and Materials (Volume 835)
• Pages: 260-264
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.835.260
• Online since: May 2016
• Authors: Mukhametkali Musagalievich Mataev, M.R. Abdraimova, Zh.D. Batyrbekova, A.M. Madiyarova
• Keywords: Calorimetry, Ferrites, Heat Capacity, Oxides, Thermodynamic Functions

References

[1] Y. Tokura and S. Seki. Multiferroics with Spiral Spin Orders. Adv. Mater. 22 (2010) 1554. (www. MaterialsViews. com).

DOI: 10.1002/adma.200901961

[2] V.A. Ivanov, T.G. Aminov, V.M. Novgorodsev and V.V. Kalinnikov, Spintronics and spintronic materials. Bull. Acad. Sci. Chem. series, 11 (2004) 2255-2303.

[3] S. Valencia, Z. Konstantinovic, D. Schmitz, A. Gaupp, L. Balcells and B. Martínez, Interfacial effects in manganite thin films with different capping layers of interest for spintronic applications. Phys. Rev. В. 84 (2011).

DOI: 10.1103/physrevb.84.024413

[4] S.W. Cheong and M. Mostovoy, Multiferroics: a magnetic twist for ferroelectricity. Nature Mater. 6 (2007) 13. (https: /books. google. kz).

DOI: 10.1038/nmat1804

[5] R. Ramesh and N.A. Spaldin, Multiferroics: progress and prospects in thin films, Nature Mater. 6 (2007) 21. (https: /books. google. kz).

DOI: 10.1038/nmat1805

[6] L.Y. Gavrilova, T.V. Aksenov and V.A. Cherepanova, Phase equilibriums and crystalline structure of complex oxides in Ln-M-Fe-O (M-Ca, Sr) system. Inorg. Chem. J. 53(6) (2008) 1027-1033.

[7] M.K. Aldabergenov, M.M. Mataev and A.T. Baibosynova, Calculation of manganates formation enthalpies and Gibbs energies. Bull. Eurasian Univ. 1(2000) 136-140. (http: /www. akademiyanauk. kz/).

[8] B.K. Kasenov, A.T. Oralova, B.Z. Nurgaliyev and M.M. Mataev, Thermodynamic functions of LnBaMn2O5, 5 (Ln-La, Nd, Gd, Ho, Er, Lu) in the range between 298. 15 and 673 K. J. Phys. Chem. 70(5) (1996) 944-947.

[9] M.M. Mataev, N.O. Myrzahmetova, N.A. Zhumanova, Zh.K. Kuanysheva, M.A. Nurbekova and M.R. Abdraimova, Synthesis and X-Ray Scattering Analysis of Complex Manganites and Ferrites. World Appl. Sci. J. 21(7) (2013) 1032-1035.

[10] M.M. Mataev, N.O. Myrzahmetova, D. Zh. Nuketaeva, A. Zhumanova, Zh.K. Kuanysheva, M.A. Nurbekova and M.R. Abdraimova, Heat Capacity and Thermodynamic Functions of Complex Manganites and Ferrites in Temperature Range 298. 15 - 673K, Middle East J. Sci. Res. (MEJSR), 4(1) (2013).

[11] E.S. Platunov, S.E. Buravoy, V.V. Kurepin and G.S. Petrov, Thermophysical measurements and instruments. Leningrad: Mech. Eng, 1986, p.256.

[12] V.P. Spiridonov and L.V. Lopatkin, Mathematical processing of experimental data. Moscow: Publishing House of the Moscow State University, 1970. p.221.

[13] R.A. Robie, В.S. Hewingway and J.К. Fisher, Thermodynamic Properties of Minerals and Related Substances at 298, 15 and (105Paskals) Pressure and at Higher Temperatures, Washington: United States Government Printing Office, 1978, pp: 456.

[14] V.P. Kumok, The problem of matching methods for assessing thermodynamic characteristics. Direct and reverse problems of chemical thermodynamics. Novosibirsk: publishing Science. 1987, p.108.