Multicomponent Molecular Conductors with Supramolecular Assembly: Iodine-Containing Neutral Molecules as Building Blocks

Abstract

Lewis acid−base interactions between anions and iodine-containing neutral molecules have been utilized in order to accomplish multicomponent molecular conductors with supramolecular assemblies. In the presence of diiodoacetylene (DIA), p-bis(iodoethynyl)benzene (pBIB), and/or tetraiodoethylene (TIE), several cation-radical salts of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) or ethylenedithiotetrathiafulvalene (EDT-TTF) are prepared by galvanostatic oxidation with such supporting electrolytes as Cl-, Br-, I-, and/or AuBr2-. Crystal structures of these salts solved by the X-ray diffraction method exhibit novel donor (BEDT-TTF or EDT-TTF) arrangements and supramolecular assemblies made of the anions and the neutral molecules (DIA, pBIB, and/or TIE). Transport properties show that these salts range from metal to semiconductor. Several interesting properties such as a curious band dispersion and high anisotropy in resistivity are also observed. Some packing motifs for the description of the supramolecular assemblies have been revealed by an overview of these crystal structures.