The salt [ET](3)[Sb-2(L-tart)(2)](CH3CN)-C-. (1) has been obtained by electrocrystallization of the organic donor bis(ethylendithio)tetrathiafulvalene (ET or BEDT-TTF) in the presence of the chiral anionic complex [Sb-2(L-tart)(2)](2-) (L-tart = (2R,3R)-(+)-tartrate). This salt crystallizes in the chiral space group P2(1)2(1)2(1) (a = 11.145(2) Angstrom, b = 12.848(2) Angstrom, c = 40.159(14) Angstrom, V = 5750.4(14) Angstrom(3), Z = 4) and is formed by alternating layers of the anions and of the organic radicals in a noncentrosymmetric alpha-type packing. This compound shows a room temperature electrical conductivity of similar to1 S(.)cm(-1) and semiconducting behavior with an activation energy of similar to85 meV. Analysis of the magnetic susceptibility and band structure, however, suggests that this compound should be a narrow band gap semiconductor.