(BEDT-TTF) 2 Cu 2 (HCOO) 5 : An Organic-Inorganic Hybrid Conducting Magnet.

A dual-functional organic-inorganic hybrid (BEDT-TTF)2 Cu2 (HCOO)5 ( 1 ) (BEDT-TTF=bis(ethylenedithio)tetrathiafulvalene) was obtained through the electrochemical oxidation of neutral BEDT-TTF in the presence of an ammonium salt of the one-dimensional copper-formate framework [(C2 H5 )3 NH]2 Cu2 (HCOO)5 in a C6 H5 Cl-C2 H5 OH solution. Compound  1 was composed of organic donor BEDT-TTF+0 ⋅5 in a θ-phase arrangement and Jahn-Teller distorted (4,4) grid anion sheets [Cu2 (HCOO)5 - ] n with S= 1/2. We identified the material as a semiconductor with values of σ 300K =10-1  S cm-1 . The anion sheet is a coordination isomer of [Cu2 (HCOO)5 - ] n and, compared with the starting material, shows antiferromagnetic behavior as the well-known inorganic Cu-O, Co-O square layers for creating inorganic conducting magnets. Long-range antiferromagnetic ordering was observed at 8.0 K.