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arXiv · 0905.0337

Low Temperature Crystal Structure and 57Fe Moessbauer Spectroscopy of Sr3Sc2O5Fe2As2

Marcus Tegel·Inga Schellenberg·Franziska Hummel·Rainer Poettgen·Dirk Johrendt
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Abstract

The crystal structure of the layered iron arsenide Sr3Sc2O5Fe2As2 was determined between 300 and 10 K. The lattice parameters of the tetragonal cell decrease anisotropically according to delta(c)/c : delta(a)/a = 4.2, which results in a slight flattening of the As-Fe-As bond angle within the FeAs layers. No indication of a structural instability could be detected. 57Fe Moessbauer spectroscopic data show a single signal at 4.2, 77, and 298 K, respectively, subjected to quadrupole splitting. The isomer shift increases from 0.36(1) mm/s at 298 K to 0.49(1) mm/s at 4.2 K. No indication for magnetic ordering was found.

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Marcus Tegel, Inga Schellenberg, Franziska Hummel, Rainer Poettgen, Dirk Johrendt. 2009-05-04. Low Temperature Crystal Structure and 57Fe Moessbauer Spectroscopy of Sr3Sc2O5Fe2As2. https://arxiv.org/abs/0905.0337

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