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arXiv · 0902.0971

Pressure-Induced Effects on the Structure of the FeSe Superconductor

Jasmine N. Millican·Daniel Phelan·Evan L. Thomas·Juscelino B. Leao·Elisabeth Carpenter
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Abstract

A polycrystalline sample of FeSe, which adopts the tetragonal PbO-type structure (P4/nmm) at room temperature, has been prepared using solid state reaction. We have investigated pressure-induced structural changes in tetragonal FeSe at varying hydrostatic pressures up to 0.6 GPa in the orthorhombic (T = 50 K) and tetragonal (T = 190 K) phases using high resolution neutron powder diffraction. We report that the structure is quite compressible with a Bulk modulus around 31 GPa to 33 GPa and that the pressure response is anisotropic with a larger compressibility along the c-axis. Key bond angles of the SeFe4 pyramids and FeSe4 tetrahedra are also determined as a function of pressure.

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Jasmine N. Millican, Daniel Phelan, Evan L. Thomas, Juscelino B. Leao, Elisabeth Carpenter. 2009-04-01. Pressure-Induced Effects on the Structure of the FeSe Superconductor. https://doi.org/10.1016/j.ssc.2009.02.011

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