A new program has been developed for ab initio crystal structure determination from powder diffraction data (X‐ray and neutron). It uses global‐optimization algorithms to solve the structure by performing trials in direct space. It is a modular program, capable of using several criteria for evaluating each trial configuration (e.g. multi‐pattern). It is also modular in the description of the crystal content, with the possibility of describing building blocks in the sample, such as polyhedra or molecules, and with automatic adaptive handling of special positions and sharing of identical atoms between neighbouring building blocks. It can therefore find the correct structure without any assumption about the connectivity of the building blocks and is suitable for any kind of material. Several optimization algorithms (simulated annealing, parallel tempering) are available, with the possibility of choosing the convergence criterion as a combination of available cost functions. This program is freely available for Linux and Windows platforms; it is also fully `open source', which, combined with an object‐oriented design and a complete developer documentation, ensures its future evolution.

A wide variety of metal borohydrides, MBH, have been discovered and characterized during the past decade, revealing an extremely rich chemistry including fascinating structural flexibility and a wide range of compositions and physical properties. Metal borohydrides receive increasing interest within the energy storage field due to their extremely high hydrogen density and possible uses in batteries as solid state ion conductors. Recently, new types of physical properties have been explored in lanthanide-bearing borohydrides related to solid state phosphors and magnetic refrigeration. Two major classes of metal borohydride derivatives have also been discovered: anion-substituted compounds where the complex borohydride anion, BH, is replaced by another anion, i.e. a halide or amide ion; and metal borohydrides modified with neutral molecules, such as NH, NHBH, NH, etc. Here, we review new synthetic strategies along with structural, physical and chemical properties for metal borohydrides, revealing a number of new trends correlating composition, structure, bonding and thermal properties. These new trends provide general knowledge and may contribute to the design and discovery of new metal borohydrides with tailored properties towards the rational design of novel functional materials. This review also demonstrates that there is still room for discovering new combinations of light elements including boron and hydrogen, leading to complex hydrides with extreme flexibility in composition, structure and properties.

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The fabrication of thin-film Fe(2)O(3) photoanodes from the spray pyrolysis of Fe(III)-containing solutions is reported along with their structural characterization and application to the photoelectrolysis of water. These films combine good performance, measured in terms of photocurrent density, with excellent mechanical stability. A full investigation into the effects that modifications of the spray-pyrolysis method, such as the addition of dopants or structure-directing agents and changes in precursor species or carrier solvent, have on the performance of the photoanodes has been realized. The largest photocurrents were obtained from photoanodes prepared from ferric chloride precursor solutions, simultaneously doped with Ti(4+) (5%) and Al(3+) (1%). Doping with Zn(2+) also shows promise, cathodically shifting the onset potential by approximately 0.22 V.