ME(3)TTF-PO3H2, A REDOX PHOSPHONIC ACID AND ITS MONOANILINIUM SALT [PHNH(3)(-PO(OHO-], THE ELECTROCRYSTALLIZED NEUTRAL (ZWITTERIONIC) PI-RADICAL [ME(3)TTF-PO(OHO-](.+), AND THEIR ASSOCIATED LAMELLAR CONSTRUCTIONS IN THE SOLID-STATE()][ME(3)TTF)

The reaction of Me(3)TTFLi (TTF = tetrathiafulvalene) with CIP(O)-(OEt )(2) followed by hydrolysis with Me(3)SiBr affords the novel pi-donor molecule trimethyltetrathiafulvalenylphosphonic acid (Me(3)TTF-PO3H2) in a partially oxidized form. Subsequent reduction and neutralization with aniline gives the corresponding phosphonate monoanilinium salt. A unique hydrogen-bonded hexagonal net is identified within the lamella r structure of [PhNH(3)(+)][Me(3)TTF-PO(OHO-], which is described by a nalogy with the anti-CaSi2 structure type. Electrocrystallization of t he former salt yields single crystals of a neutral (zwitterionic) pi r adical, formulated as [Me(3)TTF-PO(OHO-](.+). Their structure reveals the presence of hydrogen-bonded molecular ribbons whose association cr eates a novel layered architecture similar to that obtained within rad ical cation salts of pi-donor molecules of larger spatial extension. T he analysis of the calculated HO-MO-HOMO intermolecular interaction en ergies demonstrates that these slabs contain strong pi-pi intermolecul ar interactions despite the nonexistence of any 2D network of short S ... S contacts. The spin susceptibility of [Me(3)TTF-PO-(OHO-](.+), de termined by single-crystal ESR measurements, is characteristic of trip let excitons, the origin of which may be understood from the electroni c structure of the compound.