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A combined diffraction and EXAFS study of LaCoO3 and La0.5Sr0.5Co0.75Nb0.25O3 powders

Published online by Cambridge University Press:  28 February 2017

E. A. Efimova*
Affiliation:
Joint Institute for Nuclear Research, 141980 Dubna, Russia
V. V. Sikolenko
Affiliation:
Joint Institute for Nuclear Research, 141980 Dubna, Russia REC “Functional nanomaterials” Immanuel Kant Baltic Federal University, 236041 Kaliningrad, Russia
D. V. Karpinsky
Affiliation:
Scientific-Practical Material Research Center NAS Belarus, 220072 Minsk, Belarus
I. O. Troyanchuk
Affiliation:
Scientific-Practical Material Research Center NAS Belarus, 220072 Minsk, Belarus
S. Pascarelli
Affiliation:
European Synchrotron Radiation Facility, BP 220, 38043 Grenoble, France
C. Ritter
Affiliation:
Institut Laue-Langevin, Grenoble, France
M. Feygenson
Affiliation:
Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
S. I. Tiutiunnikov
Affiliation:
Joint Institute for Nuclear Research, 141980 Dubna, Russia
V. Efimov
Affiliation:
Joint Institute for Nuclear Research, 141980 Dubna, Russia
*
a)Author to whom correspondence should be addressed. Electronic mail: efea@mail.ru

Abstract

A combination of neutron diffraction, synchrotron X-ray diffraction, and high-resolution extended X-ray absorption fine structure measurements has been used to clarify the correlations between long- and local-range structural distortions across the spin-state transition in powders of LaCoO3 and La0.5Sr0.5Co0.75Nb0.25O3. The analysis of the diffraction data has revealed that the isotropic thermal parameters of Co–O bond abnormally increase below 100 K in both samples, while the temperature dependence of the average Co–O bond lengths is linear from 10 to 300 K. We also have found that the Co–O bond lengths are larger in La0.5Sr0.5Co0.75Nb0.25O3, as compared with the ones in LaCoO3. The X-ray absorption data showed an anomalous decrease of the Co–O bond lengths only for LaCoO3, in contrast to the bond length values obtained by diffraction. The structural anomalies observed by spectroscopy measurements are discussed in terms of the spin-state transition model.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2017 

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References

Fornasini, P., Beccara, G., Dalba, R., Grisenti, A., Sanson, M., and Vaccari, M. (2004). “Local dynamics, anharmonicity, and thermal expansion extended x-ray-absorption fine-structure measurements of copper,” Phys. Rev. B 70, 174301.CrossRefGoogle Scholar
Haverkort, M. V., Hu, Z., Cezar, J. C., Burnus, T., Hartmann, H., Reuther, M., Zobel, C., Lorenz, T., Tanaka, A., Brookes, N. B., Hsieh, H. H., Lin, H. J., Chen, C. T., and Tjeng, L. H. (2006). “Spin state transition in LaCoO3 studied using soft X-ray absorption spectroscopy and magnetic circular dichroism,” Phys. Rev. Lett. 97, 176405.CrossRefGoogle ScholarPubMed
Herklotz, A., Rata, A. D., Schultz, L., and Doerr, K. (2009). “Reversible strain effect on the magnetization of LaCoO3 films,” Phys. Rev. B 79, 092409.Google Scholar
Knížek, K., Jirak, Z., Hejtmanek, J., Veverka, M., Marysko, M., and Maris, G. (2005). “Structural anomalies associated with the electronic and spin transitions in LnCoO3 ,” Eur. Phys. J. B 47, 213.Google Scholar
Korotin, M. A., Anisimov, V. I., Khomskii, D. I., Ezhov, S. Y., Solovyev, I. V., Khomskii, D. I., and Sawatzky, G. A. (1996). “Intermediate-spin state and properties of LaCoO3 ,” Phys. Rev. B 54, 5309.Google Scholar
Kuzmin, A. (1995). “EDA: EXAFS data analysis software package,” Physica B 208/209, 175.Google Scholar
Maris, G., Ren, Y., Volotchaev, V., Zobel, C., Lorenz, T., and Palstra, T. (2003). “Evidence for orbital ordering in LaCoO3 ,” Phys. Rev. B 67, 224423.Google Scholar
Pandey, S., Kumar, A., and Prabhakaran, D. (2008). “Investigation of the spin state of Co in LaCoO3 at room temperature: ab initio calculations and high-resolution photoemission spectroscopy of single crystals,” Phys. Rev. B 77, 045123.Google Scholar
Pirogov, A. N., Teplykh, E. A., Voronin, V. I., Balagurov, A. M., Pomjakushin, V. Y., Sikolenko, V. V., and Filonova, E. A. (1999). “Ferro- and antiferromagnetic ordering in LaMnO3+ ,” Phys. of the Sol. State 41, 91.CrossRefGoogle Scholar
Podlesnyak, A., Streule, S., Mesot, J., Medarde, M., Pomjakushina, E., Conder, K., Tanaka, A., Haverkort, M. V., and Khomskii, D. I. (2006). “Spin-state transition in LaCoO3: direct neutron spectroscopic evidence of excited magnetic states,” Phys. Rev. Lett. 97, 247208.Google Scholar
Potze, R. H., Sawatzky, G. A., and Abbate, M. (1995). “Possibility for an intermediate-spin ground state in the charge-transfer material SrCoO3 ,” Phys. Rev. B 51, 11501.Google Scholar
Radaelli, P. G. and Cheong, S. W. (2002). “Structural phenomena associated with the spin-state transition in LaCoO3 ,” Phys. Rev. B 66, 094408.Google Scholar
Rodriguez-Carvajal, J. (1993). “Recent advances in magnetic structure determination by neutron powder diffraction,” Physica B 192, 55.Google Scholar
Sazonov, A. P., Troyanchuk, I. O., Gamari-Seale, H., Sikolenko, V. V., Stefanopoulos, K. L., Nicolaides, G. K., and Atanassova, Y. K. (2009). “Neutron diffraction study and magnetic properties of La1−x Ba x CoO3 (x = 0.2 and 0.3),” J. Phys.: Condens. Mater 21, 156004.Google Scholar
Senaris-Rodriguez, M. A. and Goodenough, J. B. (1995). “Magnetic and transport properties of the system La1−x Sr x CoO3−δ (0 < x ≤ 0.50),” J. Solid State Chem. 118, 323.Google Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chaleogenides,” Acta Crystallogr. Sect. A 32, 751.Google Scholar
Sikolenko, V., Efimov, V., Efimova, E., Sazonov, A., Ritter, C., Kuzmin, A., and Troyanchuk, I. (2009). “Neutron diffraction studies of structural and magnetic properties of niobium doped cobaltites,” J. Phys.: Condens. Matter 21, 436002.Google ScholarPubMed
Sundaram, N., Jiang, Z., Anderson, I. E., Belanger, D. P., Booth, C. H., Bridges, F., Mitchell, J. F., Proffen, T., and Zheng, H. (2009). “Local structure of La1−x Sr x CoO3 determined from EXAFS and neutron pair distribution function studies,” Phys. Rev. Lett. 102, 026401.Google Scholar
Troyanchuk, I., Balagurov, A., Sikolenko, V., Efimov, V., and Sheptyakov, D. (2013a). “Very large magnetoresistance and spin state transition in Ba-doped cobaltites,” J. Appl. Phys. 113, 053909.Google Scholar
Troyanchuk, I., Bushinsky, M., Sikolenko, V., Efmov, V., Ritter, C., Hansen, T., and Többens, D. M. (2013b). “Pressure induced antiferromagnet–ferromagnet transition in La0.5Ba0.5CoO2.8 cobaltite,” Eur. Phys. J. B 86, 435.Google Scholar
Zobel, C., Kriener, M., Bruns, D., Baier, J., Grüninger, M., Lorenz, T., Reutler, P., and Revcolevschi, A. (2002). “EXAFS and X-ray diffraction study of LaCoO3 across the spin-state transition,” Phys. Rev. B 66, R020402.Google Scholar