BIS(1,4-DITHIAFULVEN-6-YL)-SUBSTITUTED AND TETRAKIS(1,4-DITHIAFULVEN-6-YL)-SUBSTITUTED TETRATHIAFULVALENES AND DIHYDROTETRATHIAFULVALENES -A NOVEL CLASS OF PLANAR DONOR MOLECULES WITH MULTIPLE REDOX FUNCTIONALITIES AND THE DEMONSTRATION OF A NOVEL TYPE OF 2-DIMENSIONAL ASSOCIATION IN THE SOLID-STATE

The planar molecule 3c, one of the new, extended sulfur-rich planar an alogues of TTF whose strong electron-donating abilities are reported, has been engaged electrochemically into a semiconducting (E(a) = 170 m eV) 1:1 ClO4- salt which presents a remarkably high room-temperature c onductivity (sigma(RT) = 0.38 S cm-1) for a fully charge-transferred s alt. The analysis of its crystal structure reveals a unique pattern of overlap, a manifestation of the shape and planar character of the mol ecule, leading to a novel type of two-dimensional association for cati on radical salts. Tight-binding calculations demonstrate that two-dime nsional electron delocalization is in fact occurring in this slab, a c onsequence of the actual electronic conjugation within the entire mole cule.