The first organic cation-radical salt superconductor (Tc= 4 K) with an organometallic anion: superconductivity, synthesis and structure of κL-(BEDT-TTF)2Cu(CF3)4·TCE

Abstract
Superconductivity at ambient pressure with onset Tc= 4.00 ± 0.05 K is reported in a unique organic cation-radical salt κL-(ET)2Cu(CF3)4·TCE, [ET = bis(ethylenedithio)tetrathiafulvalene, TCE = 1,1,2-trichloroethane] with the Cu(CF3)4 species being the first Cu3+ and F containing organometallic anion in an organic superconductor.