A brief 100 year history of carbon.

Elemental carbon has been known from time immemorial in its forms of diamond and graphite, while the Industrial Revolution was powered by coal. The molecular structures of diamond and graphite were established following the inception of X-ray crystallography while the complex natures of charcoal and coal have been investigated for 100 years. Recent developments in activated charcoal are described in an article in this issue of Science Progress.

Femtosecond studies: observing transition states and other ultra-short-lived species.

To celebrate 2015 as the 'International Year of Light', this article offers a short survey of the progress made since the award of the Nobel Prize of 1999 to Professor Ahmed Zewail for his pioneering work on taking the timescale for observation of light-induced events down to the femtosecond level. Developments have included the extension of studies (i) to larger molecules, leading up to biological systems; (ii) the increased range of detection methods of transient species from the UV-Vis to the infrared region; (iii) the introduction of Raman spectroscopy to augment IR studies; (iv) examination of combination events to supplement dissociation events; (v) the interrogation of transient structures by X-ray absorption spectroscopy; (vi) the study of reactions taking place at solid surfaces.

100 years of X-ray crystallography.

The developments in crystallography, since it was first covered in Science Progress in 1917, following the formulation of the Bragg equation, are described. The advances in instrumentation and data analysis, coupled with the application of computational methods to data analysis, have enabled the solution of molecular structures from the simplest binary systems to the most complex of biological structures. These developments are shown to have had major impacts in the development of chemical bonding theory and in offering an increasing understanding of enzyme-substrate interactions.

Carbon dioxide as a polymer feedstock.

This review describes the progress made over the last 45 years since the seminal paper by Inoue's group in Tokyo on the utilisation of CO2 as a component of a polymerising system. This approach, rapidly taken up by others, focused initially on the copolymerisation of CO2 with an epoxide to yield a polycarbonate of high molecular weight. The initial catalysts for this process were based on organozinc compounds; these were extended to zinc phenoxides and then a series of metal-centred compounds, particularly metal porphyrins where the central metal was aluminium, cobalt, chromium, copper, manganese and various lanthanides.

Direct observation of oxygen depletion and product formation during photocatalysis at a TiO2 surface using scanning electrochemical microscopy.

Using scanning electrochemical microscopy (SECM) we have measured quantitatively the depletion of O2 during the photodegradation of 4-chlorophenol at supported TiO2 films for the first time and established the connection between Cl-formation and O2 depletion rates.

A microelectrochemical actinometer for scanning electrochemical microscopy studies of photochemical processes.

A new in situ electrochemical actinometry method has been developed and used to determine the light flux through a quartz fibre, employed in a scanning electrochemical microscopy (SECM) system developed to study the kinetics of interfacial photochemical processes. In this system an ultramicroelectrode (UME) probe is positioned with high precision at a known distance close to the end of the fibre, through which light is guided, and used to detect reactants or products of the ongoing photochemical process. The microelectrochemical actinometer was developed using the well-known liquid phase potassium ferrioxalate actinometer.

2-D soft ferromagnet based on [Wv(CN)8]3- and CuII with a Tc of 34 K.

Self-assembly of [Cu(tetren)]2+ (tetren = tetraethylenepentamine) and [W(CN)8]3- in acidic aqueous solution yields the double-layered square grid cyanide-bridged polymer of ((tetrenH5)0.8CuII4[Wv(CN)8](4).7.

A novel dizinc bridged hydroxamate model for hydroxamate inhibited zinc hydrolases.

Reaction of Zn(OAc)(2).2H2O with tmen leads to the formation of [Zn(tmen)(OAc)2] (I) which reacts with benzohydroxamic acid to form Zn(BA)2.H2O (II) and the novel dizinc hydroxamate bridged complex [Zn2(mu-OAc)2(OAc)(mu-BA)(tmen)] (III), which may also be prepared by self-assembly and whose structure closely mimics that of the native hydroxamate inhibited Aeromonas proteolytica aminopeptidase.