Collection

2016 Nobel Prize in Chemistry

The 2016 Nobel Prize in Chemistry has been won by Jean-Pierre Sauvage, Fraser Stoddart and Ben Feringa, for their work on the design and synthesis of tiny molecular machines. This Collection, drawn from Nature Research journals, highlights some of the important contributions to this field.

Image credit: Nik Spencer / Nature

Review, news and comment

The way forward for a field in its infancy is to focus on complexity and integrated systems that may lead to emergent phenomena, suggests J. Fraser Stoddart at Northwestern University.

Feature | | Nature Chemistry

Making muscle is easy, Philip Ball reports. All it takes is a molecular needle and thread.

News | | Nature

A molecular motor has first to generate movements that are not swamped by Brownian motion, a dominant force at that scale, and cannot exploit angular momentum as a means of directional control. Despite these constraints, David Leigh and colleagues have developed a system that consumes a single chemical fuel to power a molecular machine that achieves continuous rotary motion as long as the fuel is present, and does not require any further chemical input or external stimulus. The motor consists of two interlocked molecular rings, the smaller of which (the macrocycle) is continuously transported directionally around the larger (the cyclic molecular track) when powered by irreversible reactions of a chemical fuel. Directionality is achieved via asymmetry in reaction rates of the chemical fuel added to the track, forcing the macrocycle to continue travelling in the same direction, rather than reversing towards the previous reactive point.

News & Views | | Nature

An autonomous chemically driven artificial molecular machine uses information acquired by allosteric interactions combined with an exergonic reaction to know which way to go.

News & Views | | Nature Nanotechnology

An axle-shaped molecule pumps charged rings from solution into an alkyl collection unit, a mechanism that, in two repetitive cycles, takes the system increasingly further from equilibrium.

News & Views | | Nature Nanotechnology

A small molecule that mimics the sequence-specific peptide synthesis of nature's ribosomes paves the way for more elaborate artificial molecular synthesizers.

News & Views | | Nature Chemistry

A supramolecular polymer made of thousands of bistable [c2]daisy chains amplifies individual nanometric displacements up to the micrometre-length scale, in a concerted process reminiscent of muscular cells.

News & Views | | Nature Nanotechnology

Research

The miniaturization of integrated circuits could stall in 20 years or so, when current technologies will scale down no further. Miniaturization beyond that point might be possible with DRAMs (dynamic random access memories, a concept derived from molecular electronics), the use of nanowires, and defect-tolerant architectures. Small, error-tolerant memory circuits combining these features have already been demonstrated, but this approach moves to another level with the development of a 160,000-bit molecular electronic memory, roughly analogous to a projected 'year 2020' DRAM circuit. The circuit still has large numbers of non-working memory bits, but they are readily identified and isolated; the working bits can then be configured as a fully functional random access memory. In a News Feature, Philip Ball looks at the computer architectures needed to exploit hyper-dense molecular memories.

Letter | | Nature

The construction and operation of interlocked molecular machines often rely on the mutual recognition of different building blocks through a range of non-covalent interactions. Researchers have now shown that the versatility of bipyridinium systems can be increased by taking advantage of the complexes formed between their radical cations; with this approach they have been able to make electrochemically switchable bi- and tristable rotaxanes.

Article | | Nature Chemistry

Biological rotary motors can alter their mechanical function by changing the direction of rotary motion. Now, researchers have designed a synthetic light-driven rotary motor in which the direction of rotation can be reversed on command by changing the chirality of the molecular motor through base-induced epimerization.

Article | | Nature Chemistry

Any future artificial transporters and robots operating at the nanoscale are likely to require molecules capable of directional translational movement over a surface. Even the design of such molecules is a daunting task, however, as they need to be able to use light, chemical or electrical energy to modulate their interaction with the surface in a way that generates directional motion. Kudernac et al. now unveil just such a molecule, made by attaching four rotary motor units to a central axis. Inelastic electron tunnelling induces conformational changes in the rotors and propels the molecule across a copper surface. By changing the direction of the rotary motion of individual motor units, the self-propelling molecular 'four-wheeler' structure can follow random or preferentially linear trajectories. This design provides a starting point for the exploration of more sophisticated molecular mechanical systems, perhaps with complete control over their direction of motion.

Letter | | Nature

The piston-like, translational motion of a molecular shuttle — a process that is fundamental to many mechanically interlocked molecular switches and machines — has now been demonstrated to occur inside the highly organized and dense structure (containing approximately 1021 shuttles per cm3) of a metal–organic framework material.

Article | | Nature Chemistry

Avoiding equal probability for clockwise and anticlockwise rotation is essential for the function of molecular motors, and both biological and synthetic systems take advantage of chirality to control the rotary direction. Now it has been shown, by integrating two rotor moieties in a symmetric meso motor design, that light-driven unidirectional rotary motion can be achieved in an achiral system.

Article | | Nature Chemistry

Solid-state fluorescent materials show promise for potential applications in security and anti-counterfeiting technologies. Here, the authors report a heterorotaxane which has found application in security inks with highly tunable solid-state fluorescence through supramolecular encapsulation.

Article | Open Access | | Nature Communications

When supplied with redox energy, a dumbbell-shaped molecule can take small charged molecules from solution and thread them around an oligomethylene chain.

Article | | Nature Nanotechnology

A molecular motor has first to generate movements that are not swamped by Brownian motion, a dominant force at that scale, and cannot exploit angular momentum as a means of directional control. Despite these constraints, David Leigh and colleagues have developed a system that consumes a single chemical fuel to power a molecular machine that achieves continuous rotary motion as long as the fuel is present, and does not require any further chemical input or external stimulus. The motor consists of two interlocked molecular rings, the smaller of which (the macrocycle) is continuously transported directionally around the larger (the cyclic molecular track) when powered by irreversible reactions of a chemical fuel. Directionality is achieved via asymmetry in reaction rates of the chemical fuel added to the track, forcing the macrocycle to continue travelling in the same direction, rather than reversing towards the previous reactive point.

Letter | | Nature

Control of motion at the molecular level is an integral requirement for the development of future nanoscale machinery. Now, governed by the fundamental reactivity principles of organometallic chemistry, a biaryl rotor is shown to exhibit 360° unidirectional rotary motion driven by the conversion of two simple fuels.

Article | | Nature Chemistry