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arXiv · 1509.04851

Structural transition and superconductivity in hydrothermally synthesized FeX (X = S, Se)

Ursula Pachmayr·Natalie Fehn·Dirk Johrendt
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Abstract

Tetragonal beta-FeSe obtained by hydrothermal reaction is not superconducting and transforms to a triclinic structure at 60 K unlike superconducting FeSe from solid state synthesis, which becomes orthorhombic at 90 K. In contrast, tetragonal iron sulphide FeS from hydrothermal synthesis is superconducting at 4.8 K but undergoes no structural transition. Our results suggest that the absence of superconductivity in hydrothermally synthesized FeSe may be associated to the low-temperature structure with zigzag chains of iron atoms, which is different from the known orthorhombic Cmme structure of superconducting FeSe.

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Ursula Pachmayr, Natalie Fehn, Dirk Johrendt. 2015-09-16. Structural transition and superconductivity in hydrothermally synthesized FeX (X = S, Se). https://doi.org/10.1039/c5cc07739g

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