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Title: Stability of Jahn-Teller distortion in LaMnO{sub 3} under pressure: An x-ray absorption study

Abstract

The local environment of manganese atoms in LaMnO{sub 3} under pressure up to 15.3 GPa has been studied by x-ray absorption spectroscopy. For pressures below 8 GPa, no change is detected within the MnO{sub 6} octahedra. Above this pressure a continuous reduction of the long Mn-O distance takes place, however, the octahedral distortion persists over the whole pressure range. At 15.3 GPa the average Jahn-Teller splitting of the distances is reduced by about one-third, indicating that a total removal of the local Jahn-Teller distortion would occur only for pressures around 30 GPa, where metallization is reported to take place. A hysteresis in the long distance reduction is observed down to ambient pressure, suggesting the coexistence of MnO{sub 6} distorted and undistorted units.

Authors:
; ; ; ; ;  [1];  [2];  [3];  [4]
  1. Institut Neel, UPR 2940-CNRS, 25 av. des Martyrs, Boite Postale 166, 38042 Grenoble, France and Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo (Brazil)
  2. (Brazil)
  3. (France)
  4. (Argentina)
Publication Date:
OSTI Identifier:
20976670
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevB.75.052103; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; ABSORPTION SPECTROSCOPY; HYSTERESIS; JAHN-TELLER EFFECT; LANTHANUM COMPOUNDS; MANGANATES; MANGANESE; PRESSURE RANGE GIGA PA; PRESSURE RANGE MEGA PA 10-100; REDUCTION; X RADIATION; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Ramos, Aline Y., Tolentino, Helio C. N., Souza-Neto, Narcizo M., Itie, Jean-Paul, Morales, Liliana, Caneiro, Alberto, Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo, Brazil and Departamento de Fisica dos Materiais e Mecanica, DFMT-IF-USP, Sao Paulo, SP, Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex, and Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica and Universidad Nacional de Cuyo, 8400 S.C. de Bariloche. Stability of Jahn-Teller distortion in LaMnO{sub 3} under pressure: An x-ray absorption study. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.052103.
Ramos, Aline Y., Tolentino, Helio C. N., Souza-Neto, Narcizo M., Itie, Jean-Paul, Morales, Liliana, Caneiro, Alberto, Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo, Brazil and Departamento de Fisica dos Materiais e Mecanica, DFMT-IF-USP, Sao Paulo, SP, Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex, & Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica and Universidad Nacional de Cuyo, 8400 S.C. de Bariloche. Stability of Jahn-Teller distortion in LaMnO{sub 3} under pressure: An x-ray absorption study. United States. doi:10.1103/PHYSREVB.75.052103.
Ramos, Aline Y., Tolentino, Helio C. N., Souza-Neto, Narcizo M., Itie, Jean-Paul, Morales, Liliana, Caneiro, Alberto, Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo, Brazil and Departamento de Fisica dos Materiais e Mecanica, DFMT-IF-USP, Sao Paulo, SP, Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex, and Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica and Universidad Nacional de Cuyo, 8400 S.C. de Bariloche. Thu . "Stability of Jahn-Teller distortion in LaMnO{sub 3} under pressure: An x-ray absorption study". United States. doi:10.1103/PHYSREVB.75.052103.
@article{osti_20976670,
title = {Stability of Jahn-Teller distortion in LaMnO{sub 3} under pressure: An x-ray absorption study},
author = {Ramos, Aline Y. and Tolentino, Helio C. N. and Souza-Neto, Narcizo M. and Itie, Jean-Paul and Morales, Liliana and Caneiro, Alberto and Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo, Brazil and Departamento de Fisica dos Materiais e Mecanica, DFMT-IF-USP, Sao Paulo, SP and Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex and Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica and Universidad Nacional de Cuyo, 8400 S.C. de Bariloche},
abstractNote = {The local environment of manganese atoms in LaMnO{sub 3} under pressure up to 15.3 GPa has been studied by x-ray absorption spectroscopy. For pressures below 8 GPa, no change is detected within the MnO{sub 6} octahedra. Above this pressure a continuous reduction of the long Mn-O distance takes place, however, the octahedral distortion persists over the whole pressure range. At 15.3 GPa the average Jahn-Teller splitting of the distances is reduced by about one-third, indicating that a total removal of the local Jahn-Teller distortion would occur only for pressures around 30 GPa, where metallization is reported to take place. A hysteresis in the long distance reduction is observed down to ambient pressure, suggesting the coexistence of MnO{sub 6} distorted and undistorted units.},
doi = {10.1103/PHYSREVB.75.052103},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 5,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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