New Li-Ethylenediamine-Intercalated Superconductor Lix(C2H8N2)yFe2-zSe2 with Tc = 45 K

A new iron-based superconductor Lix(C2H8N2)yFe2-zSe2 with \(T_{\text{c}} = 45\) K has successfully been synthesized via intercalation of dissolved lithium metal in ethylenediamine. The distance between neighboring Fe layers is 10.37 Å and much larger than those of FeSe with \(T_{\text{c}} = 8\) K and KxFe2Se2 with \(T_{\text{c}} \sim 30\) K. It seems that the high-\(T_{\text{c}}\) of Lix(C2H8N2)yFe2-zSe2 is caused by the possible two-dimensional electronic structure due to the large \(c\)-axis length.