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Redetermination of the distorted perovskite Nd(0.53)Sr(0.47)MnO(3).

ABSTRACT: Neodymium strontium manganese oxide with ideal composition Nd(0.5)Sr(0.5)MnO(3) was reported to have two different structure models. In one model, the x coordinate of an O atom is at x > 1/2, while in the other model the x-coordinate of this atom is at x < 1/2. Difference-density maps around this O atom obtained from the current redetermination clearly show that the structure with the O atom at x < 1/2 result in a more satisfactory model than that with x > 1/2. The title compound with a refined composition of Nd(0.53?(5))Sr(0.47?(5))MnO(3) is a distorted perovskite-type structure with site symmetries 2mm for the statistically occupied (Nd, Sr) site and for the above-mentioned O atom, .2/m. for the Mn atom and ..2 for a second O-atom site. In contrast to previous studies, the displacement factors for all atoms were refined anisotropically.

SUBMITTER: Makita R

PROVIDER: S-EPMC2959730 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Redetermination of the distorted perovskite Nd(0.53)Sr(0.47)MnO(3).

Makita Ryoko R Tanaka Kiyoaki K Kubota Masato M Murakami Youichi Y

Acta crystallographica. Section E, Structure reports online 20081022 Pt 11

Neodymium strontium manganese oxide with ideal composition Nd(0.5)Sr(0.5)MnO(3) was reported to have two different structure models. In one model, the x coordinate of an O atom is at x > 1/2, while in the other model the x-coordinate of this atom is at x < 1/2. Difference-density maps around this O atom obtained from the current redetermination clearly show that the structure with the O atom at x < 1/2 result in a more satisfactory model than that with x > 1/2. The title compound with a refined ...[more]

PMID: 21580813

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