Origin of the non-linear pressure effects in perovskite manganites: Buckling of Mn-O-Mn bonds and Jahn-Teller distortion of the MnO6 octahedra induced by pressure

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:322

Article

Chen, Z.¹  Tyson, T. A.¹  Ahn, K. H.¹  Zhong, Z.²  Hu, J.³ 

[1] New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA

[2] Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA

[3] Univ Chicago, NSLS X17C, Upton, NY 11973 USA

关键词: High pressure;    Perovskite manganite;    Metal-insulator transition;   

DOI  :  10.1016/j.jmmm.2010.05.027

来源: Elsevier

【 摘 要 】

High-pressure resistivity and X-ray diffraction measurements were conducted on La0.85MnO3-delta at similar to 6 and similar to 7 GPa, respectively. At low pressures the metal-insulator transition temperature (TMI) increases linearly up to a critical pressure, P*similar to 3.4 GPa, followed by reduction in T-MI at higher pressure. Analysis of the bond distances and bond angles reveals that ab and width increase drives the increase in TMI below P*. The reduction in TMI at higher pressures is found to result from Jahn-Teller distortions of the MnO6 octahedra. The role of an harmonic interatomic potentials is discussed. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

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