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arXiv · 1511.04393

Intercalation effect on hyperfine parameters of Fe in FeSe superconductor with Tc = 42 K

Sergii I Shylin·Vadim Ksenofontov·Stefan J Sedlmaier·Simon J Clarke·Simon J Cassidy·Gerhard Wortmann·Sergey A Medvedev·Claudia Felser
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Abstract

57Fe-Mossbauer spectra of superconducting beta-FeSe, the Li/NH3 intercalate product and a subsequent sample of this intercalate treated with moist He gas have been measured in temperature range 4.7 - 290 K. A correlation is established between hyperfine parameters and critical temperature Tc in these phases. A strong increase of isomer shift upon intercalation is explained by a charge transfer from the Li/NH3 intercalate to the FeSe layers resulting in an increase of Tc up to 42 K. A significant decrease of the quadrupole splitting above 240 K has been attributed to diffusive motion of Li+ ions within the interlamellar space.

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Sergii I Shylin, Vadim Ksenofontov, Stefan J Sedlmaier, Simon J Clarke, Simon J Cassidy, Gerhard Wortmann, Sergey A Medvedev, Claudia Felser. 2015-11-13. Intercalation effect on hyperfine parameters of Fe in FeSe superconductor with Tc = 42 K. https://doi.org/10.1209/0295-5075%2F109%2F67004

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