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Title: Morin-like spin canting in the magnetic CaFe{sub 5}O{sub 7} ferrite: A combined neutron and Mössbauer study

Abstract

Magnetic structure of CaFe{sub 5}O{sub 7} ferrite has been studied jointly from neutron powder diffraction data and spectroscopic Mössbauer measurements in the thermal range from 5 to 500 K. This coupled work highlights three distinct magnetic domains around two specific temperatures: T{sub M}=125 K and T{sub N}=360 K. The latter corroborates the structural monoclinic-orthorhombic transition previously reported by transmission electron microscopy techniques and X-ray thermodiffractometry. Complementary heat capacity measurements have confirmed this first order transition with a sharp peak at 360 K. Interestingly, this large study has revealed a second magnetic transition associated to a spin rotation at 125 K similar to this one reported by Morin in α-Fe{sub 2}O{sub 3} hematite at T{sub M}=260 K. - Graphical abstract: Magnetic structure of CaFe{sub 5}O{sub 7} ferrite has been studied jointly from neutron powder diffraction data and spectroscopic Mössbauer measurements in the thermal range from 5 to 500 K. This coupled work highlights three distinct magnetic domains around two specific temperatures: T{sub M}=125 K and T{sub N}=360 K. Interestingly, this large study has revealed a magnetic transition associated to a spin rotation at 125 K similar to this one reported by Morin in α-Fe{sub 2}O{sub 3} hematite at T{sub M}=260 K.

Authors:
; ; ;  [1];  [2];  [1];  [3];  [1]
  1. Laboratoire CRISMAT ENSICAEN UMR CNRS 6508, 6 Boulevard du Maréchal Juin, 14050 Caen Cedex 04 (France)
  2. Institut des Molécules et Matériaux du Mans, IMMM UMR CNRS 6283, Avenue Olivier Messiaen, 72085 Le Mans (France)
  3. Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9 (France)
Publication Date:
OSTI Identifier:
22658215
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 247; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CALCIUM COMPOUNDS; EXPERIMENTAL DATA; FERRITES; IRON OXIDES; MORIN; NEUTRON DIFFRACTION; SPECIFIC HEAT; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Delacotte, C., Bréard, Y., Caignaert, V., Hardy, V., Greneche, J.M., Hébert, S., Suard, E., and Pelloquin, D. Morin-like spin canting in the magnetic CaFe{sub 5}O{sub 7} ferrite: A combined neutron and Mössbauer study. United States: N. p., 2017. Web. doi:10.1016/J.JSSC.2016.12.021.
Delacotte, C., Bréard, Y., Caignaert, V., Hardy, V., Greneche, J.M., Hébert, S., Suard, E., & Pelloquin, D. Morin-like spin canting in the magnetic CaFe{sub 5}O{sub 7} ferrite: A combined neutron and Mössbauer study. United States. doi:10.1016/J.JSSC.2016.12.021.
Delacotte, C., Bréard, Y., Caignaert, V., Hardy, V., Greneche, J.M., Hébert, S., Suard, E., and Pelloquin, D. Wed . "Morin-like spin canting in the magnetic CaFe{sub 5}O{sub 7} ferrite: A combined neutron and Mössbauer study". United States. doi:10.1016/J.JSSC.2016.12.021.
@article{osti_22658215,
title = {Morin-like spin canting in the magnetic CaFe{sub 5}O{sub 7} ferrite: A combined neutron and Mössbauer study},
author = {Delacotte, C. and Bréard, Y. and Caignaert, V. and Hardy, V. and Greneche, J.M. and Hébert, S. and Suard, E. and Pelloquin, D.},
abstractNote = {Magnetic structure of CaFe{sub 5}O{sub 7} ferrite has been studied jointly from neutron powder diffraction data and spectroscopic Mössbauer measurements in the thermal range from 5 to 500 K. This coupled work highlights three distinct magnetic domains around two specific temperatures: T{sub M}=125 K and T{sub N}=360 K. The latter corroborates the structural monoclinic-orthorhombic transition previously reported by transmission electron microscopy techniques and X-ray thermodiffractometry. Complementary heat capacity measurements have confirmed this first order transition with a sharp peak at 360 K. Interestingly, this large study has revealed a second magnetic transition associated to a spin rotation at 125 K similar to this one reported by Morin in α-Fe{sub 2}O{sub 3} hematite at T{sub M}=260 K. - Graphical abstract: Magnetic structure of CaFe{sub 5}O{sub 7} ferrite has been studied jointly from neutron powder diffraction data and spectroscopic Mössbauer measurements in the thermal range from 5 to 500 K. This coupled work highlights three distinct magnetic domains around two specific temperatures: T{sub M}=125 K and T{sub N}=360 K. Interestingly, this large study has revealed a magnetic transition associated to a spin rotation at 125 K similar to this one reported by Morin in α-Fe{sub 2}O{sub 3} hematite at T{sub M}=260 K.},
doi = {10.1016/J.JSSC.2016.12.021},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 247,
place = {United States},
year = {Wed Mar 15 00:00:00 EDT 2017},
month = {Wed Mar 15 00:00:00 EDT 2017}
}
  • Li{sub 3}Fe{sub 2}(PO{sub 4}){sub 3} has been actively studied as a Lithium ion battery cathode material for the next-generation energy storage application. Here, we have investigated the changes of magnetic coupling between two different magnetic sub-lattices in Li{sub 3}Fe{sub 2}(PO{sub 4}){sub 3} with x-ray diffraction (XRD), superconducting quantum interference device (SQUID), and Mössbauer spectroscopy measurements. The experimental XRD pattern was analyzed using Rietveld refinement, confirming single phase. In order to investigate the magnetic property, the SQUID measurement under applied field of 5 T was performed between 4.2 and 295 K. From the temperature-dependent zero-field-cooled and field-cooled magnetization curves, we observed the magnetizationmore » decreasing with increasing temperature up to T{sub min} = 13 K, at which the magnetization showed a minimum value. With continuing increase in temperature, the magnetization starts increasing with a maximum value at T{sub max} = 28 K and beyond T{sub max}, the magnetization decreases with the further increase in temperature. Based on the experimentally measured Mössbauer spectra, we identified that the ratios of first and sixth to second and fifth absorption lines were identical around T{sub min}, while with increasing temperature the area of second and fifth absorption line rapidly decreased up to T{sub max}. Our study suggests that the spin canting angle between the applied field and hyperfine field of Li{sub 3}Fe{sub 2}(PO{sub 4}){sub 3} is constant up to T{sub min}. However, the spin canting angle starts decreasing with increasing temperature, reaching a minimum value at T{sub max}, and beyond T{sub max} it is increasing. We expect that around T{sub max}, the ferrimagnetically coupled spin arrangement is appeared to be collinear along the applied field direction under applied field of 5 T.« less
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  • No abstract prepared.
  • By microscopic studies it is found that CaFe/sub 5/O/sub 7/ (often represented by CW/sub 3/F) does not disappear by decomposition to three solid phases at about 1050{sup 0}C, as suggested by previous phase diagrams. Instead it disappears by melting at about 1100{sup 0}C. On cooling, part of the liquid solidifies to a eutectic structure, wustite + Ca/sub 2/Fe/sub 2/O/sub 5/ (often represented by C/sub 2/F). A revision of Turkdogan's oxygen potential-temperature diagram is proposed in order to account for the new information.
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