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تسجيل مستخدم جديدStructural phase transition in TmxFe1-xSe0.85 (Tm = Mn and Cu) and its relation to superconductivity
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In this letter, we report the results of detailed studies on Mn- and Cu-substitution to Fe-site of beta-FeSe, namely MnxFe1-xSe0.85 and CuxFe1-xSe0.85. The results show that with only 10 at% Cu-doping the compound becomes a Mott insulator. Detailed temperature dependent structural analyses of these Mn- and Cu-substituted compounds show that the structural transition, which is associated with the changes in the building block FeSe4 tetrahedron, is essential to the occurrence of superconductivity in beta-FeSe.
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