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Positive charges lower, and negative charges raise the freezing temperature of supercooled water on a pyroelectric surface, as well as affecting at which interface nucleation takes place.

The field of organocatalysis has grown rapidly in the past decade to become, along with metal catalysis and biocatalysis, a third pillar of asymmetric catalysis. Here, progress in the use of organocatalytic cascade reactions for total synthesis is reviewed. The elegance and efficiency of such cascades mean that they have emerged as a powerful tool in synthetic organic chemistry.

A Brønsted acid co-catalyst is the key to the synthesis of furans by alkene cross-metathesis.

Exposing supramolecular filaments to X-rays results in spontaneous and reversible crystalline ordering.

A linear molecule containing three bipyridine ligands can be wrapped around a single metal-ion template to form an open-knot complex. The loose ends of the knot can be 'tied' together through esterification or olefin-metathesis reactions to form closed knots that do not unravel when the metal template is removed.

The uptake of ammonia by a covalent–organic framework (COF) containing a high density of Lewis-acidic boron sites has been found to be significantly greater than that exhibited by other state-of-the-art porous materials. The ammonia can be removed by heating under vacuum and the structural integrity of the COF is maintained during adsorption/desorption cycles.

The synthesis of interlocked compounds such as catenanes and rotaxanes has undergone much development in recent years, but molecular knots are still relatively hard to make. It has now been shown that a linear bipyridine oligomer can fold around a single zinc-ion template to form a complex that can be cyclized to give a molecular trefoil knot.

A methodology for describing local electronic transmission through bridging molecules between metallic electrodes is presented. Its application to simple alkane, phenyl and cross-conjugated systems highlights an unexpected number of cases whereby ‘through space’, rather than ‘through bond’ terms dominate and that interference effects coincide with the reversal of ring currents.

The movement of oxygen ions through materials is important in electrolytes and separation membranes, but is rare at lower temperatures. Two different low-temperature diffusion pathways are revealed during the reduction process of CaFeO_2.5 to CaFeO₂. The two pathways are significantly different, resulting in anisotropy.

Silicon-based polymers have been assembled into honeycomb films that exhibit good flexibility, stability and thermal conductivity, showing great promise for industrial applications.

Replacing readily hydrolysable ester linkages with amides in a natural adjuvant has resulted in not only more stable, but significantly more active and less toxic analogues.

The financial crisis that continued to grip the world in 2009 has brought the question of who should pay for scientific research — and what it should set out to achieve — into sharper focus than ever.

Chemical reactions of fullerenes and metallofullerenes lined up inside single-walled carbon nanotubes can be monitored at the atomic scale inside an aberration-corrected transmission electron microscope.

Yttrium-based catalysts can be used to stitch together two different lactone monomers in an alternating fashion to produce polyesters with well-defined primary structures. The ability to control the sequence of building blocks in polymers with increasing levels of precision offers new opportunities for tailoring the properties of designer synthetic macromolecules.

The stereochemical lability of cycloalkylzinc reagents combined with a large difference in reactivity between epimers has been exploited to form a wide variety of interesting organic compounds with both high yields and diastereoselectivities.

Michelle Francl wonders why people almost inevitably draw scientists as men with weird hair and glasses, and why there is no such thing as a 'draw a lawyer' test.