Recent special issues

In their Guest Editorial (http://doi.org/whc) in this second special issue on Mathematical Crystallography in Acta Crystallographica Section A: Foundations and Advances, Massimo Nespolo and Gregory McColm describe the current activities of the IUCr Commission on Mathematical Crystallography. A recent and fruitful cooperation with US mathematicians has resulted in crystallographic special sessions at sectional meetings of the American Mathematical Society and specialized conferences of the Society for Industrial and Applied Mathematics (SIAM). In particular, the 2013 SIAM Conference on Mathematical Aspects of Materials Science in Philadelphia, USA, was the occasion to gather articles, partly arising from that meeting, for this issue. Perhaps befitting this digital age, this is a virtual issue, spanning three regular issues, but all appearing during the International Year of Crystallography. The result is a wide but necessarily incomplete selection from the panorama of research activities, which demonstrates the actuality and the importance of mathematical crystallography for every researcher interested in the periodic structure of matter, whatever the dimension and geometry.

A virtual issue featuring Coordination Polymers, with an introduction by Len Barbour, was published in Acta Crystallographica Section C: Structural Chemistry in July 2014 (http://tinyurl.com/coordinationpolymers). The past two decades have witnessed a veritable explosion of reports detailing the solid-state structures of coordination compounds consisting of conceptually infinite one-dimensional chains, two-dimensional nets and three-dimensional frameworks. The concepts involved are relatively simple; crystalline coordination polymers are most often formed from solutions containing metal ions and bridging ligands. The seemingly unlimited opportunities for preparing novel coordination polymers arise not only from obvious choices that influence structural topology (i.e. bridging-ligand geometry and metal-ion coordination mode) but also from a range of other factors, some of which can be quite subtle. The collection of articles selected for this virtual issue serves to showcase the amazing diversity of the field.

A collection of articles from the IUCr Diffraction Data Deposition Working Group (DDD WG) has been published in the October 2014 issue of Acta Crystallographica Section D: Biological Crystallography (http://tinyurl.com/diffractiondata). The DDD WG was commissioned by the IUCr in 2011 with John Helliwell as chair to examine the benefits and feasibility of archiving raw diffraction images in crystallography. The group initiated spirited discussions on this subject on the CCP4 mailing list, held workshops to gather input on the idea of archiving raw images, and encouraged wide analysis of the ideas and challenges. In this issue, several researchers in the field of macromolecular structure determination have written a collection of articles discussing the archiving of diffraction images, what it would make possible, and what challenges it poses. The DDD WG hopes that these articles will stimulate extensive debate and action in the crystallographic community.

The Journal of Synchrotron Radiation's latest special issue (http://tinyurl.com/storagerings) explores Diffraction-Limited Storage Rings (DLSRs) and New Science Opportunities. Guest-edited by Mikael Eriksson and J. Friso van der Veen, the issue contains 22 articles connecting recent advances in accelerator technology with the new science that can be done at upcoming and future DLSRs. The cover illustration shows an artistic impression of the new MAX IV facility, currently under construction in Lund, Sweden, and one of a new generation of storage-ring-based synchrotron light sources employing a multibend achromat lattice to reach emittances in the few hundred pm rad range in a circumference of a few hundred metres. (Image courtesy of FOJAB arkitekter.)

Just some of the special issues in the pipeline: Energy Materials (Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials), CCP4 2014 Study Weekend - Two Way Street - Complementary Methods (Acta Crystallographica Section D: Biological Crystallography), Molecular Parasitology - Advances in Biology and Supporting Drug Discovery (Acta Crystallographica Section F: Structural Biology Communications), X-ray Radiation Damage to Biological Crystalline Samples (Journal of Synchrotron Radiation) and Free-Electron Lasers (Journal of Synchrotron Radiation).