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This work presents two new amphiphilic molecules derived from the tetrathiafulvalene (TTF) cycle. The purpose of this work is to realize a controlled in-plane molecular architecture. In order to obtain well organized macrocycles at the air-water interface we have added to the TTF cycle four long alkyl chains, each with an acid (or ester) group. Compound I has been designed to form a regular paving in the polar plane whereas for compound II an identical arrangement in the hydrophobic plane is predicted. The synthesis and thermodynamic stability of the monolayers are investigated for both molecules. The results show that these macrocycles are lying flat on the water surface: this is the first step in two-dimensional molecular engineering.

We study an electrochemical method of obtaining conducting Langmuir-Blodgett films as radical cation salts of dialkylthioethylenedithiotetrathiofulvalence (TTF) derivatives. We show an electro-oxidation of the TTF moiety through the films. The mixed-valence state responsible for the conductivity phenomenon is generally not obtained except with iodide electrolyte, under potentials larger than 0.45 V SCE and after a thermal treatment.

Langmuir-Blodgett films of a long chain tetrathiafulvalene (TTF) donor derivative (BEDT-TTFC 18 ) were deposited onto different substrates for investigating several physical properties before and after doping by a few oxidizing agents. In the presence of ICl vapour, two different phases, insulating and semi-conducting, were obtained, as shown by electron spin resonance, IR and Raman spectroscopies. From these preliminary results, it seems that the doping chemical process is different from the well known charge transfer occurring in organic conductors.