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

A new iron-based superconductor Li-x(C2H8N2)(y)Fe2-zSe2 with T-c 45 K has successfully been synthesized via intercalation of dissolved lithium metal in ethylenediamine. The distance between neighboring Fe layers is 10.37 angstrom and much larger than those of FeSe with Tc = 8 K and KxFe2Se2 with T-c similar to 30 K. It seems that the high-T-c of Li-x(C2H8N2)(y)Fe2-zSe2 is caused by the possible two-dimensional electronic structure due to the large c-axis length.