Original scientific paper

Study of Bi2Fe4O9 by Mössbauer effect

D- Hanžel ; Institute “Jožef Stefan”, Ljubljana and the Faculty of Science and Technology, Ljubljana
A. Moljk ; Institute “Jožef Stefan”, Ljubljana and the Faculty of Science and Technology, Ljubljana

Abstract

The antiferromagnetic Bi_2Fe_4O_9 was studied between 8 and 550 K by the use of Mössbauer effect. Transition temperature was determined at T_N = 253 + 3 K, while effective magnetic field, extrapolated to O K, amounts to 535 ± 5 kG for actahedral and to 485 ± 5 kG for tetrahedral iron sites. The temperature dependence of the sublattice magnetization does not agree satisfactorily with the Brillouin curve for S = 5/2. In the region 0.76 < T/ T_N < 0.97, the sublattice magnetization is represented as M (T) = M (O) D (I - T/T_N) β with β_octa = 0.29 and β_tet = 0.31. From the quadrupole splitting above T_N and from the calculated field gradient, nuclear quadrupole moment of the excited state of iron on octahedral site is estimated as (57Q) = 0.16 ± 0.03 b.

Keywords

Hrčak ID:

321987

URI

https://hrcak.srce.hr/321987

Publication date:

6.8.1973.

Article data in other languages: slovenian

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