Silver coordination compounds with a family of ditopic ligands of varying flexibility : about chains, rings, helices and polycatenanes

While searching possibilities of creating “supramolecular architectures” in which different metal cations can be caught by an organic ligand, envisaging catalysis, formation of polyelectrolytes, and other applications, it was a matter of fact that certain ligands are able to form more than one supramolecular array in the same reaction vessel [1], even some other crystals, acting like “living structures” changing form when left in the reaction mixture [2-4]. “Supramolecular polymorphism” or “Supramolecular isomerism” is a common phenomenon in coordination polymer. Network isomerism or polymorphism appears and disappears almost without a clear idea of what happened. Just as in the same way is pretty difficult to predict the formation of a crystalline array based on the knowledge of the organic ligand, the metal salt and the crystallization conditions that are employ. A previous work of Dr. Robin in our group, for instance, shown the difficulty arised on the control of the co-crystallized solvent in a family of silver(I) compounds which crystallize concomitantly in water [2]. That place two relates question: working in similar circumstances concerning the reactants and reaction conditions, will the number of possible topological combinations infinite or rather quantized? If the answer is affirmative than, until which point can we gain control over the forces involved in the complexation process and further crystallization of the products? The crystallization of silver(I) network polymers can be achieved by different methods, but two main approaches are the most common ones: i) varying the solvent, ii) varying temperature. Other techniques were implemented for several authors, we tried almost all of them and the results will be discussed in this thesis.