Study of (Ln,Sr)(Fe,Co)O3-δ type CMR materials by 57 Co emission Mössbauer spectroscopy

Z. Homonnay, Z. Klencsár, E. Kuzmann, Z. Németh, P. Rajczy, K. Kellner, G. Gritzner, A. Vértes

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Emission Mössbauer experiments on La0.8Sr0.2CoO3-δ, Eu0.8Sr0.2CoO3-δ, and La0.8Sr0.257Fe0.05Co0.95O 3.δ were carried out using 57Co dopant in order to see how the spectra may be interpreted on the basis of the results of transmission Mössbauer studies on the same or similar compounds. It was found that when the material contains a small amount of iron, the emission and transmission Mössbauer spectra match each other at room temperature, which lead to the conclusion that iron does not form clusters in the cobaltate perovskite but is rather monoatomically dispersed in the lattice. The iron free cobaltates showed lower isomer shifts than the ones containing iron, which is proposed to be due to the very low concentration of nucleogenic 57Fe, tending to acquire an oxidation state higher than +3, and to the different electric transport properties of the host material. The difference between magnetic structures observed at low temperatures in transmission and emission experiments as well as in La- and Eu-containing materials were attributed to different oxygen defect structures. It is generally concluded that in the investigated materials, the 57Fe probe formed by an EC decay of 57Co in an emission Mössbauer experiment serves as a normal 57Fe probe having the oxygen coordination number of the mother 57Co.

Original languageEnglish
Pages (from-to)165-170
Number of pages6
JournalSolid State Phenomena
Volume90-91
Publication statusPublished - 2003

Fingerprint

Emission spectroscopy
Iron
iron
spectroscopy
Oxygen
probes
Defect structures
Experiments
Magnetic structure
oxygen
coordination number
Isomers
Perovskite
Transport properties
low concentrations
isomers
transport properties
Doping (additives)
Oxidation
Temperature

Keywords

  • Colossal magnetoresistance
  • Emission Mössbauer spectroscopy
  • Europium-strontium-co baltate
  • Lanthanum-strontium-cobaltate
  • Perovskite

ASJC Scopus subject areas

  • Materials Science(all)
  • Physics and Astronomy (miscellaneous)
  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Study of (Ln,Sr)(Fe,Co)O3-δ type CMR materials by 57 Co emission Mössbauer spectroscopy. / Homonnay, Z.; Klencsár, Z.; Kuzmann, E.; Németh, Z.; Rajczy, P.; Kellner, K.; Gritzner, G.; Vértes, A.

In: Solid State Phenomena, Vol. 90-91, 2003, p. 165-170.

Research output: Contribution to journalArticle

@article{946c00dcb12d4f3fb150d79fe41974f4,
title = "Study of (Ln,Sr)(Fe,Co)O3-δ type CMR materials by 57 Co emission M{\"o}ssbauer spectroscopy",
abstract = "Emission M{\"o}ssbauer experiments on La0.8Sr0.2CoO3-δ, Eu0.8Sr0.2CoO3-δ, and La0.8Sr0.257Fe0.05Co0.95O 3.δ were carried out using 57Co dopant in order to see how the spectra may be interpreted on the basis of the results of transmission M{\"o}ssbauer studies on the same or similar compounds. It was found that when the material contains a small amount of iron, the emission and transmission M{\"o}ssbauer spectra match each other at room temperature, which lead to the conclusion that iron does not form clusters in the cobaltate perovskite but is rather monoatomically dispersed in the lattice. The iron free cobaltates showed lower isomer shifts than the ones containing iron, which is proposed to be due to the very low concentration of nucleogenic 57Fe, tending to acquire an oxidation state higher than +3, and to the different electric transport properties of the host material. The difference between magnetic structures observed at low temperatures in transmission and emission experiments as well as in La- and Eu-containing materials were attributed to different oxygen defect structures. It is generally concluded that in the investigated materials, the 57Fe probe formed by an EC decay of 57Co in an emission M{\"o}ssbauer experiment serves as a normal 57Fe probe having the oxygen coordination number of the mother 57Co.",
keywords = "Colossal magnetoresistance, Emission M{\"o}ssbauer spectroscopy, Europium-strontium-co baltate, Lanthanum-strontium-cobaltate, Perovskite",
author = "Z. Homonnay and Z. Klencs{\'a}r and E. Kuzmann and Z. N{\'e}meth and P. Rajczy and K. Kellner and G. Gritzner and A. V{\'e}rtes",
year = "2003",
language = "English",
volume = "90-91",
pages = "165--170",
journal = "Solid State Phenomena",
issn = "1012-0394",
publisher = "Scientific.net",

}

TY - JOUR

T1 - Study of (Ln,Sr)(Fe,Co)O3-δ type CMR materials by 57 Co emission Mössbauer spectroscopy

AU - Homonnay, Z.

AU - Klencsár, Z.

AU - Kuzmann, E.

AU - Németh, Z.

AU - Rajczy, P.

AU - Kellner, K.

AU - Gritzner, G.

AU - Vértes, A.

PY - 2003

Y1 - 2003

N2 - Emission Mössbauer experiments on La0.8Sr0.2CoO3-δ, Eu0.8Sr0.2CoO3-δ, and La0.8Sr0.257Fe0.05Co0.95O 3.δ were carried out using 57Co dopant in order to see how the spectra may be interpreted on the basis of the results of transmission Mössbauer studies on the same or similar compounds. It was found that when the material contains a small amount of iron, the emission and transmission Mössbauer spectra match each other at room temperature, which lead to the conclusion that iron does not form clusters in the cobaltate perovskite but is rather monoatomically dispersed in the lattice. The iron free cobaltates showed lower isomer shifts than the ones containing iron, which is proposed to be due to the very low concentration of nucleogenic 57Fe, tending to acquire an oxidation state higher than +3, and to the different electric transport properties of the host material. The difference between magnetic structures observed at low temperatures in transmission and emission experiments as well as in La- and Eu-containing materials were attributed to different oxygen defect structures. It is generally concluded that in the investigated materials, the 57Fe probe formed by an EC decay of 57Co in an emission Mössbauer experiment serves as a normal 57Fe probe having the oxygen coordination number of the mother 57Co.

AB - Emission Mössbauer experiments on La0.8Sr0.2CoO3-δ, Eu0.8Sr0.2CoO3-δ, and La0.8Sr0.257Fe0.05Co0.95O 3.δ were carried out using 57Co dopant in order to see how the spectra may be interpreted on the basis of the results of transmission Mössbauer studies on the same or similar compounds. It was found that when the material contains a small amount of iron, the emission and transmission Mössbauer spectra match each other at room temperature, which lead to the conclusion that iron does not form clusters in the cobaltate perovskite but is rather monoatomically dispersed in the lattice. The iron free cobaltates showed lower isomer shifts than the ones containing iron, which is proposed to be due to the very low concentration of nucleogenic 57Fe, tending to acquire an oxidation state higher than +3, and to the different electric transport properties of the host material. The difference between magnetic structures observed at low temperatures in transmission and emission experiments as well as in La- and Eu-containing materials were attributed to different oxygen defect structures. It is generally concluded that in the investigated materials, the 57Fe probe formed by an EC decay of 57Co in an emission Mössbauer experiment serves as a normal 57Fe probe having the oxygen coordination number of the mother 57Co.

KW - Colossal magnetoresistance

KW - Emission Mössbauer spectroscopy

KW - Europium-strontium-co baltate

KW - Lanthanum-strontium-cobaltate

KW - Perovskite

UR - http://www.scopus.com/inward/record.url?scp=0038397477&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0038397477&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0038397477

VL - 90-91

SP - 165

EP - 170

JO - Solid State Phenomena

JF - Solid State Phenomena

SN - 1012-0394

ER -