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arXiv · 1508.01654

Topotactic synthesis of a new BiS2-based superconductor Bi2(O,F)S2

Tomoyuki Okada·Hiraku Ogino·Jun-ichi Shimoyama·Kohji Kishio
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Abstract

A new BiS2-based superconductor Bi2(O,F)S2 was discovered. This is a layered compound consisting of alternate stacking structure of rock-salt-type BiS2 superconducting layer and fluorite-type Bi(O,F) blocking layer. Bi2(O,F)S2 was obtained as the main phase by topotactic fluorination of undoped Bi2OS2 using XeF2, which is the first topotactic synthesis of an electron-doped superconductor via reductive fluorination. With increasing F-content, a- and c-axis length increased and decreased, respectively, and Tc increased up to 5.1 K.

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Tomoyuki Okada, Hiraku Ogino, Jun-ichi Shimoyama, Kohji Kishio. 2015-08-07. Topotactic synthesis of a new BiS2-based superconductor Bi2(O,F)S2. https://doi.org/10.7567/apex.8.023102

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