Reviews & Analysis

Recently, individual organic molecules have been imaged with atomic resolution using non-contact atomic force microscopy with functionalized tips and scanning tunnelling hydrogen microscopy. The resulting applications of these techniques and further improvements of ultra-high spatially resolved molecular investigations are discussed in this Perspective.

Arranging polymers into well-defined shapes endows them with specific properties; but although it is routinely achieved in nature, accurate origami has proved challenging with synthetic polymers. A surprisingly simple folding strategy has now been described.

Many different kinds of switchable molecules and materials are based on transition metal ions, but similar properties are also possible in organic materials. Now, two separate studies reveal new insights into the ability of organic radicals to associate reversibly and cooperatively in the solid state, and in so doing create bistable, hysteretic materials.

After two decades of research, the efficiency of dye-sensitized solar cells seems to have reached a plateau. Now, changing both electrolyte and dye opens up new opportunities that offer the hope that the efficiency ceiling can be broken.

Two readily accessible synthetic building blocks are shown to form a quadruply hydrogen-bonded heterodimer that exhibits exceptional stability and offers new opportunities for the construction of supramolecular assemblies and polymers.

Phenalenyl — a triangular neutral radical consisting of three adjacent benzene rings — and π-conjugated derivatives based on the same motif, can be viewed as 'open-shell graphene fragments'. This Perspective discusses their electronic-spin structures, the properties that arise from their unpaired electrons, and highlights their potential applications for molecular spin devices.

The radical–radical association reaction between hydroxyl and nitrogen dioxide plays a central role in atmospheric chemistry but has challenged experimentalists for decades. A study now measures all reactants and products and largely settles the issue.

An unusual cyclization reaction to form alkylarenes — which are important chemical feedstocks — from alkanes is mediated by an iridium catalyst.

One-electron oxidation is generally expected to weaken a bond in a molecule or, on rare occasions, break it. Removing one electron from a small propellane cage has now been shown to break three lateral bonds, opening it up into an acyclic cation after a cascade of rearrangements, initiated by vibronic coupling.

Nature reduces dinitrogen under mild conditions using nitrogenases, the most active of which contains molybdenum and iron. The only abiological dinitrogen reduction catalyst that avoids the harsh conditions of the Haber–Bosch process contains just molybdenum.

The programmable and reliable hybridization of DNA strands has enabled the preparation of a wide variety of structures. This Review discusses how, in addition to these static assemblies, the process of displacing — and ultimately replacing — strands also makes possible the construction of dynamic systems such as logic gates or autonomous walkers.

Advances in transduction of electrochemical activity through surface plasmon resonance afford new opportunities for spatially and temporally resolved studies of interfaces.