MAGNETIC PHASE TRANSITIONS IN La1–xSrx Mn0.5Ni0.5O3 (0 ≤ x ≤ 0.2) PEROVSKITES
Abstract
The La1–x Srx Ni0.5Mn0.5O3 (0 ≤ x ≤ 0.2) perovskites have been studied by the methods of neutron powder diffraction and magnetization and by magnetoresistance measurement. It was shown that Ni and Mn ions are partially ordered in spite of the presence of Ni3+ ions arising from La3+ with Sr2+ substitution. The magnetic structure changes from ferromagnetic (x = 0) to antiferromagnetic (x ≥ 0.1); however, the transition temperature into the paramagnetic state is constant. Magnetoresistance in the ferromagnetic phase is large and gradually decreases with increasing temperature and Sr2+ content. The results are discussed in terms of close in value ferromagnetic and antiferromagnetic parts of Ni2+–O–Mn4+ magnetic interactions and the enforcement of 3d-O2p orbital hybridization in the magnetic field.
About the Authors
I. O. Troyanchuk
Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus,
Minsk
Russian Federation
Russian Federation
Corresponding Member, D. Sc. (Physics and Mathematics), Professor, Head of the Laboratory, Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus
M. V. Bushinsky
Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus,
Minsk
Russian Federation
Ph. D. (Physics and Mathematics), Senior researcher, Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus
Russian Federation
Ph. D. (Physics and Mathematics), Senior researcher, Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus
G. M. Chobot
Belarusian State Agrarian Technical University
Russian Federation
Ph. D. (Physics and Mathematics), Assistant Professor
Russian Federation
Ph. D. (Physics and Mathematics), Assistant Professor
A. V. Nikitin
Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus,
Minsk
Russian Federation
Junior researcher, Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus
Russian Federation
Junior researcher, Scientific and Practical Materials Research Centre of the National Academy of Sciences of Belarus
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