SYNTHESIS AND CRYSTAL-STRUCTURE OF AN ORGANIC SEMICONDUCTOR (ET)(4)[HG2I6]

A new cation-radical salt (ET)4[Hg2I6] (1), where ET is bis(ethylenedi thio)tetrathiafulvalene, has been synthesized in the system ET-HgI3--P hCl. An X-ray study of 1 (a = 41.02(5), b = 23.01(1), c = 8.233(2) Ang strom, V = 7772(3) Angstrom(3) space group Pc2(1)b, Z = 4, d(calc) = 2 .308 g cm(-3)) has established its composition, chemical formula, and the main structural features. The ET cation-radicals are packed in the conducting layer, the type of packing is alpha''; the [Hg2I6](2-) ani on has a dimeric structure. The temperature dependence of the conducti vity of the (ET)4[Hg2I6] crystals (sigma(300) = 6 Ohm(-1) cm(-1)) has a semiconducting character.