Rotaxane and pseudo-rotaxane molecules from molecular wires. Theoretical description.

Some rotaxane molecules were designed, and their electronic capabilities were studied by means of DFT calculations. The original molecular wire consists of an iron complex that comprises aromatic substituents that constitute linear chains, and this system is complemented by the addition of fullerene C unities at both extremes of the chain, which act as the stoppers of the chain. Another modification was to add a link that gives way to the mechanical bond; this link is a square molecule of bis-pyrydyl-pyridinium tetraion. An interesting effect was observed as a result of these modifications; the conductivity of the systems rises with the first substitution and even more with the second in such a way that the original semiconductor material changes to give a conductor one.