The Cultural Revolution: Ecological and Social

Our world is sick because of the bad relationship between human society and the planet and even more because of the discords within human society itself. We are slipping more and more towards ecological and social unsustainability. Both scientists and philosophers say it, and Pope Francis highlights these views in the Laudato Sì: " Doomsday predictions can no longer be met with irony or disdain. [...] The pace of consumption, waste and environmental change has so stretched the planet’s capacity that our contemporary lifestyle, unsustainable as it is, can only precipitate catastrophes". Here then, as the Pope writes, " bold cultural revolution" is needed

Light: A Very Peculiar Reactant and Product

See the light of day: Light is the fastest way of transferring energy and information through space, and in chemistry it can perform the dual role of reactant and product. Sunlight, a really unique reactant, represents our ultimate energy source. Chemists are engaged in designing systems for the conversion of light into electrical or chemical energy and vice versa to create a more sustainable way of life

Macchine molecolari

La costruzione di macchine di dimensioni molecolari è uno straordinario risultato scientifico e un obiettivo primario della nanotecnologia. Nel corso degli ultimi trent'anni, i chimici in varie parti del mondo hanno imparato a realizzare delle semplici macchine nanometriche. Anche se questi minuscoli dispositivi non sono ancora divenuti parte integrante della nostra vita quotidiana, siamo ormai alle soglie di una nuova rivoluzione industriale, capace di cambiare il nostro futuro con applicazioni innovative nella tecnologia dei materiali, nell'informatica, nella robotica e nella medicina

Artificial molecular-level machines with [Ru(bpy)3]2

A molecular-level machine is an assembly of a discrete number of molecular components (that is, a supramolecular structure) designed to perform mechanical-like movements (output) as a consequence of appropriate external stimuli (input). Like macroscopic machines, molecular-level machines are characterized by (i) the kind of energy input supplied to make them work, (ii) the kind of movement performed by their components, (iii) the way in which their operation can be controlled and monitored, (iv) the possibility to repeat the operation at will and establish a cyclic process, (v) the time scale needed to complete a cycle of operation, and (vi) the function performed. The most convenient way to supply energy to an artificial molecular-level machine is through a photochemical reaction.[Ru(bpy)3]2+(bpy=2,2′-bipyridine) can be used as a photosensitizer to power mechanical movements in machines based on pseudorotaxanes, rotaxanes and catenanes. Besides being used as an external photosensitizer,[Ru(bpy)3]2+can be incorporated in one of the machine components as a "light-fueled" motor. Three types of photochemically driven piston/cylinder systems and a photocontrollable molecular abacus are described. Other kinds of more sophisticated molecular-level machines based on rotaxanes and catenanes are proposed. The extension of the concept of machine to the molecular level is important not only for the sake of basic research, but also for the growth of nanoscience and the development of nanotechnology

Photoinduced electron flow in a self-assembling supramolecular extension cable

We report the design, bottom-up construction, characterization, and operation of a supramolecular system capable of mimicking the function played by a macroscopic electrical extension cable. The system is made up of a light-powered electron source, an electron drain, and a cable as the molecular components programmed to self-assemble by means of two distinct plug/socket junctions. Such connections are reversible and can be operated independently by orthogonal chemical inputs. In the source-connector-drain supermolecule, photoinduced electron transfer from source to drain occurs, and it can be switched off by dual-mode chemically controlled disassembling of the molecular components.Ferrer Ribera, RB.; Rogez, G.; Credi, A.; Ballardini, R.; Gandolfi, MT.; Balzani, V.; Liu, Y.... (2006). Photoinduced electron flow in a self-assembling supramolecular extension cable. Proceedings of the National Academy of Sciences. 103(49):18411-18416. doi:10.1073/pnas.060645910318411184161034