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arXiv · 0807.2296

Local structural changes in paramagnetic and charge ordered phases of Sm0.2Pr0.3Sr0.5MnO3: An EXAFS Study

K. R. Priolkar·Vishwajeet Kulkarni P. R. Sarode·S. Emura
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Abstract

Sm{0.5-x}Pr{x}Sr{0.5}MnO{3} exhibits variety of ground states as x is varied from 0 to 0.5. At an intermediate doping of x = 0.3 a charge-ordered CE type antiferromagnetic insulating (AFI) ground state is seen. The transition to this ground state is from a paramagnetic insulating (PMI) phase through a ferromagnetic metallic phase (FMM). Local structures in PMI and AFI phases of x = 0.3 sample have been investigated using Pr K-edge and Sm K-edge Extended X-ray Absorption Fine Structure (EXAFS). It can be seen that the tilting and rotation of the MnO6 octahedra about the b-axis are responsible for the charge ordered CE-type antiferromagnetic ground state at low temperatures. In addition a shift in the position of the rare earth ion along the c-axis has to be considered to account for observed distribution of bond distances around the rare earth ion.

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K. R. Priolkar, Vishwajeet Kulkarni P. R. Sarode, S. Emura. 2008-07-15. Local structural changes in paramagnetic and charge ordered phases of Sm0.2Pr0.3Sr0.5MnO3: An EXAFS Study. https://doi.org/10.1088/0953-8984%2F20%2F33%2F335227

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