ET3(MnCl3)2(EtOH)2: a new organic conductor with a perovskite structure

The title salt was obtained as fine black needles from the electrolysis of ET (ET: bis(ethylenedithio)tetrathiafulvalene) with a Mn cluster in 1,1,2-trichloroethane containing 10% of ethanol. The conductivity at room temperature was 25 S cm−1 with weakly semiconducting behavior, yet the salt kept a high conductivity down to 4 K (∼0.1 S cm−1). The manganese(II) chloride anion formed an infinite chain made of face-shared MnCl6 octahedrons, and these chains formed insulating sheets with ethanol molecules between the chains. The ET cation radicals formed α′-type conducting sheets between the insulating sheets. Such crystal structure was characterized as that of a typical hexagonal perovskite ABX3, where A equals to a bulky monocation. The magnetic behavior was reproduced by the Curie–Weiss law, which might be attributable to the face-shared MnCl6 octahedron chains.