Warwick, UK, August 2013
A total of 855 crystallographers from 50 countries met in Warwick, August 25-29, 2013, to attend the 28th European Crystallographic meeting, including almost 200 students and 74 exhibitors. Over the four days of the conference, 44 microsymposia and 16 keynote lectures presented the latest advances in all aspects of crystallography. The history of the ECA was covered in a very successful microsymposium. The Congress attendees were welcomed by the ECA President André Roodt, the Chancellor of the U. of Warwick, Richard Lambert, the Chief Scientific Adviser to the UK Government, Mark Walport, and the Editor-in-Chief of IUCr Journals, Samar Hasnain.
During the opening ceremony the 7th Max Perutz Prize was awarded to Randy J. Read, who illustrated the development and application of advanced statistical approaches to all stages of protein structure solution. A concert of brass music was provided by Warwick U. students playing in a specially formed quintet called 'The Quasi-Crystallites' (see photo). The conference closed with the beautiful lecture 'Quasi-Periodic Materials - Crystals Redefined' by the Nobel Prize laureate Dan Shechtman.
During the closing ceremony 17 Poster prizes were awarded.
Throughout the duration of the conference, all the participants had the privilege to visit the 'Two Braggs Exhibition', organized by Mike Glazer and Pam Thomas to celebrate the lives of W. H. and W. L. Bragg, bringing together a fascinating collection of historic equipment, notebooks, honours, letters, films and artwork never before seen in one exhibition. Along with this fascinating exhibition, a program of entertainment was offered to participants, with the showing of the movie 'Hidden Glory' - a play about Dorothy Hodgkin by Georgina Ferry - the film 'Driven to Diffraction', the film '50 years a winner' - made in 1965 to celebrate the 1915 Nobel prize awarded to the Braggs - the film 'El misterio de los cristales gigantes', the 'Celebration of a Centenary of Crystallographers', a special symposium to mark the Bragg Centenary, and a 'critical account on the discovery of X-ray Diffraction by Laue, Friedrich and Knipping'. The gala dinner was followed by a traditional Ceilidh dance.
In addition to the main conference, five well attended satellite meetings were held: a CIF Symposium, the European Young Crystallographers meeting, Crystallographic Information and Data Management, PDF Analysis, and Introduction to Software Development for Crystallographers.Alessia Bacchi
Methods and Techniques
In a session on Time-resolved Crystallographic Methods (MS1), L. Redecke (Germany) described how free-electron laser radiation and in vivo grown nanocrystals open new routes in structural biology and options for time-resolved experiments. Lars used very tiny (4 μm3) in vivo grown crystals, of Trypanosoma brucei cathepsin B, a protein important in structure-based drug discovery aimed at sleeping sickness. The electron density map contained readily interpretable new features and showed no serious disruption of X-ray scattering factors, a serious concern of applications of X-ray lasers in structural biology. A distinctive feature of this study was the use of femtosecond X-ray pulses. Previous studies of the time-resolved analysis of small changes in a protein crystal structure extend into the sub-nanoseconds regime using synchrotron X-ray radiation. X-ray lasers allow such studies to be extended into the femtosecond range. A. Ourmazd (USA) using mathematical techniques cogently argued that sparsely photon-populated diffraction patterns should be amenable to structure analysis. He postulated that 1012 X-ray photons per pulse would be adequate for structure analysis of most protein and virus structure studies with XFELs. This produced a vigorous discussion on the pulse fluxes required for biological FEL-based imaging. C. Dejoie (Switzerland) described using a monochromatic micro beam for serial snapshot crystallography. Laue methods allow efficient acquisition of more data at a lower X-ray flux pulse whilst preserving a strong diffraction pattern. J. Trincao (UK) described the strengths of the co-location of the Central Laser Facility, Dynamic Structural Science Consortium and the Diamond light source, and plans to form a consortium to build and access a nanocrystal beam line at the European XFEL in Hamburg. A. Nakagawa (Japan) talked about Coherent Diffraction Imaging of Spherical Biological Particles and the Japanese SACLA X-ray free electron laser studies of large spherically shaped virus single particles.Chairs: John R. Helliwell and Victor Lamzi
The session on Hybrid Approaches (MS3) included oral presentations using crystallography and cryo-electron microscopy, novel approaches in SAXS, or in situ diffraction tests. D. Wigley (UK) combined crystal structures, electron microscopy and biophysical techniques to provide insight into the stoichiometry, architecture and molecular interactions between components of the chromatin remodeling complex and the nucleosome histone core. P. Fonseca (UK) presented the structural analysis of the human proteosome, a 2.6 MDa complex within which the 19S cap promotes substrate unfolding and translocation. The sub-nonmetric cryo-EM map of the complex was analyzed by fitting known and newly determined crystal structures, providing a full backbone model of the 19S caps. N. Galatanu (France) presented a SAXS setup comprising a low background camera and a micro-source coupled with multi-layer optics providing scatter-less collimation.
J. Beale (UK) described the extracellular domain of two peptide transporters of significant pharmaceutical interest due to their ability to bind a number of clinically important drugs. A combination of SAXS, crystal structures, ab initio modelling and ensemble organization provided insight into the mechanism of these membrane proteins.
P. Aller (UK) presented the in situ plate screening and data collection procedure where dehydration of crystals is achieved though replacement of the reservoir solution by an NaCl solution (0.5-1.5 M) and overnight equilibration. Examples were shown where the diffraction improved from the range of 2.9-2.6 Å to 2.8-2.3 Å under cryo conditions when freezing after dehydration without additional cryoprotectant, or improvement from 24 Å to 11 Å resolution for a membrane protein.
The session 'Molecular Compounds under High Pressure' (MS33) gave an overview of the latest trends in high-pressure studies of molecular materials. Elena Boldyreva (Russia) described multi-component crystals (including salts, hydrates and co-crystals) having industrial and crystal engineering significance. After a review of the motivation for high-pressure analysis, Elena presented case studies of amino acids and pharmaceuticals with examples from her work and what others have reported. The examples focused on pressure-induced phenomena, including mechanisms of phase transitions, proton transfer, order-disorder structural changes and tuning of hydrogen bonds, studied by a combination of single-crystal, powder diffraction and Raman spectroscopic methods.
A talk entitled 'Bonding and Phase Change in Ammonia Borane and Lithium Amidoborane under High Pressure' was given by J. Chen (USA). With the world's increasing fuel demands and limited fossil fuel resources, research on hydrogen storage is critically important. Ammonia borane is a very promising material for hydrogen storage but industrial applications are hampered by a slow and irreversible release of gas; reversibility of the decomposition reaction could potentially be promoted by the application of pressure. The phase diagrams of the title compounds were studied as a function of pressure and temperature, using a combination of powder diffraction and Raman spectroscopy. At 3.9 GPa opaque samples of lithium amidoborane turn transparent. The lack of dihydrogen bonding in this material, which is present in the hydrogenated parent compound and facilitates hydrogen release, may prove useful for optimizing hydrogen storage properties.
K. Dziubek (Poland) presented a historic perspective on 'Volumetric Measurements in High-Pressure Crystallography', including experiments on water by Sir Francis Bacon in 1620, J. Bramah's patent for a hydraulic pump in 1975, volumetric experiments by P. W. Bridgeman in the 19th century and the introduction of the diamond anvil cell in 1958. The speaker presented the design of the piston cylinder press in use at his home laboratory, which is capable of compressing liquid and solid samples up to ca 2 GPa. Direct compression experiments in the press provide precise information on volumetric properties and phase transition pressures complementary to diffraction experiments, as demonstrated by studies of chloroform and imidazole.
In 'Pressure-Induced Polymorphism in Small Molecule Acrylic Acids', I. Oswald (UK) described investigations on acrylic acid and methacrylic acid, monomers of two industrially relevant polymers. Using single-crystal X-ray diffraction and neutron powder diffraction (on the ISIS PEARL instrument), the phase behaviour previously inferred by Raman spectroscopy was extended and clarified. For acrylic acid, a phase transition at 0.75 GPa was identified, which is associated with pleating of molecular layers. Further compression to 7.0 GPa results in an increase of the puckering of the layers. For methacrylic acid, two-phase transitions could be identified at 0.4 GPa and 1.21 GPa, respectively. Compressing the sample further to 5.0 GPa appears to lead to polymerization.
The final talk was by S. McKellar (UK) on the effect of solvent and pressure on the post-synthetic modification of a metal organic framework. (MOF). Single-crystal compression studies of St. Andrew's MOF revealed pressure-induced post-synthetic modification behaviour, in which exchange with a highly labile axial water molecule coordinated to CuII is observed. When methanol or acetonitrile are used, the exchange occurs at pressures below 0.3 GPa and hydrophilic channels are converted to hydrophobic pores. The post-synthetic modification phases are stable on releasing pressure. No ligand exchange is observed in the presence of isopropyl alcohol or ethanol, whilst exchange leads to a strain-induced collapse of the structure to an amorphous phase when using ethanol.Chairs: Yaroslav Filinchuk and Francesca Fabbiani
The session on Twinning Problems and Advantages (MS11) saw a lively mix of theory and applications, both from the small-molecule and the macromolecular crystallography worlds: it was good to hear about aspects of twinning detection and modelling (Stoeger, Rae and Abuhammad), and software development to aid twinned data processing [H. Powell (UK) and M. Lutz (Netherlands)] and realise once more that (perhaps unsurprisingly) the two crystallography (sub) communities are facing very similar problems and have questions in common.
Moreover, after this session, and when dealing with twinned crystals, the question from Powell's talk will always come to mind: are the Thompson Twins in the Tintin stories really twins, or are they just very much alike and always found together? We shall never think of twinned crystals the same way ever again!Chairs: Pietro Roversi and Loes Kroon-Batenburg
The session 'Getting More from your Electron Density' (MS29) had contributions on electron-density modification approaches to improve phase estimates from a given model, accurate electron-density modelling, and the importance of not over-restraining a model.
M. Burla (Italy) spoke about the VLD phasing algorithm, which is based on the properties of the difference Fourier synthesis and the joint probability distribution function. The efficiency of the algorithm was improved by introducing the RELAX procedure now implemented in SIR2011. Some applications include the combination of the VLD algorithm with the hybrid Fourier synthesis for ab initio phasing and its integration in a molecular replacement pipeline for automatic protein crystal structure solution.
D. Sisak (Switzerland) described a new approach for solving the structure of polycrystalline materials using a charge-flipping algorithm. Using a starting phase set for charge flipping, an approximate structure is obtained from direct-space optimization followed by a flowchart that indicates which approach is most suitable for a specific problem.
O. Sobolev (Russia) showed that large distortion of a residue in unrestrained refinement may suggest the presence of alternative conformations (ACs) for this residue. Analysis of atomic shifts in unrestrained refinement may reveal poorly ordered residues that should be checked first with electron-density maps to model in ACs.
M. Kubicki (Poland) described accurate electron-density modelling of 4-nitroimidazoles spore crystals, that revealed intermolecular interactions, (dipole-dipole, weak hydrogen bonds, H⋯H attractive contacts) and details of anharmonicity and dipole moment. Kubicki showed that these ultra-high resolution measurements can detect organic solid solutions such as A(1-x)Bx with x smaller than 4%.
M. Fronc (Slovakia) described electron-density modelling of [Cu2(μ2-I)2(2,6-dimethylpyridine)2]. This is a very ambitious project due to the presence of the very heavy atom, iodine, which bridges the two copper atoms.Chairs: Annamaria Mazzone and Claude Lecomte
The 'Total Scattering' microsym. (MS27) opened with two presentations on in situ diffraction studies of the synthesis of nanoparticles (K. M. Ø. Jensen, Denmark) and the adsorption processes in functional porous materials for medical gas delivery (P. K. Allan, UK). Jensen, winner of one of the poster prizes, will start a post-doc position at Columbia U. (USA) in Simon Billinge's group, while P. K. Allan will soon be Junior Research Fellow at U. Cambridge.
Total scattering measurements now span X-ray, neutron and electron studies of powdered or single-crystal samples, with a growing range of tools including 'real-space Rietveld', reverse Monte Carlo (RMC) and whole particle modelling, and model-independent analysis of real-space features in the data. Other contributions in the session concerned a three-dimensional pair distribution function for comparing different local ordering models in single crystals (A. Cervellino, Switzerland), Jahn-Teller symmetry switching in LaMnO3 (A. Simonov, Switzerland) and a microstructure study of Fe3O4/γ-Fe2O3 nanoparticles (C. Young, UK)Chairs: Michela Brunelli and Karena Chapman
The microsymposium on 'Anharmonic Thermal Motion' (MS30) covered thermal motion and charge-density research in general. A talk by R. Herbst-Irmer (Germany) described a multi-temperature study of an interesting structure in which one of two independent molecules was affected by anharmonicity and the other was not, a fitting example to introduce the topic. A talk by J. Bak (Poland) exploited the combination of Hirshfeld-atom and X-ray wave function refinement, using the quantum crystallography program TONTO, which now treats anharmonicity. V. Smaalen (Bayreuth, Germany) showed that today's high-resolution protein data contain additional contributions to atomic displacements beyond thermal motion, thereby fundamentally affecting our ability to extract information on static and dynamic electron-density distributions. J. Kožíšek (Slovakia) focused on data quality for faithful modelling of charge density on a copper coordination complex, and A. Hoser (Poland) discussed structural energetic and charge-density investigations of triptycene and selective derivatives.
The ratio of male and female contributors favoured the latter.Chairs: Simon Grabowsky and Birger Dittrich
In the microsym. 'Cell-Signalling Interactions and Allostery' (MS8) it was shown that in cells signals propagate between different biological active sites of a protein; and from protein to protein within cellular pathways. Allostery, a concept first devised 50 years ago by Monod, Wyman and Changeux, applies to many regulated signalling networks. Speakers in this session presented a variety of studies that illustrate signalling and allostery.
M. Delarue (France) presented crystal structures of pentameric ligand-gated ion channels, prototypical allosteric membrane receptors. He showed that ethanol stabilizes an open form of the receptor, suggesting a structural basis for neurological actions of ethanol in human receptors.
S. Savvided (Belgium) discussed how cytokines, extracellular signalling molecules, signal a receptor using a combination of biophysical, structural and computational approaches. Notably, he showed that Epstein-Barr virus intercepts a human cytokine (CSF-1) by allosteric competitive inactivation, rendering it unable to signal to its receptor.
V. Campanacci (France) presented a study of a bacterial effector that rewires membrane trafficking pathways in an infected host cell and uncovered a conserved enzymatic mechanism common to one class of toxins, which allows them to process diverse substrates.
K. Kuhnel (Germany) described a family of proteins that are crucial in an evolutionary conserved degradative pathway. She showed that these proteins have two phospholipid binding sites on a seven-bladed beta propeller structure that are adjacent but non-overlapping, suggesting how these proteins bind to membranes.
A. Echalier-Glazer (France) used crystallographic and in silico approaches to analyze the regulation of a large multi-protein complex implicated in various cellular functions through its role in the ubiquitin-proteasome pathway.Chairs: Jacqueline Cherfils and Remy Loris
In 'Organic and Inorganic Multi-component Crystals: Structure and Properties' (MS24), L. Brammer (UK) discussed studies of flexibility and chemical transformations in coordination with polymers and frameworks including gas and solvent sorption/desorption processes. Using single-crystal and powder diffraction, energy calculations and simulation of spectra, C. Wilson (UK) talked about controlling molecular assembly in the organic solid state, polymorph control and discovery from multi-component crystallization, and transferring crystal engineering to manufacturing environments. S. Galli (Italy) described using bipyrazolate ligands to construct porous coordination polymers. She showed that azole-based frameworks are chemically more stable than low density MOFs and can offer potentially comparable gas sorption properties. She also described how to use variable temperature PXRD to measure anisotropic thermal expansion properties. C. Seaton (Ireland) discussed the influence of the crystallographic environment on intermolecular proton transfer in multi-component molecular solids, using calculations on isolated molecules and clusters extracted from crystal structures. P. Wood's (UK) talk covered difficulties associated with crystal structure prediction for salts, and highlighted ways in which the Cambridge Structural Database might be used to approach some of these problems.Chairs: Nikoletta Bathori and Andrew Bond
The talks and posters in 'From Nature to Laboratory: Crystallography of Minerals and Mineral-related Materials' (MS18) covered mineral classification, structural prediction, modification of materials and new techniques for structural solution.
F. Camara (Italy) has classified Ti-silicate minerals into groups with different Ti-Si building blocks. The classification reveals relationships between structural topology and chemical composition and allows prediction of new minerals and crystal structures. F. Hatert (Belgium) showed a cation substitution mechanism occurring by oxidation in olivine-type phosphates that suggests development of new cathode materials. A. Goodwin (UK) reported on extreme negative linear compressibility (NLC) in a variety of framework materials and design principles for maximizing NLC of MOFs. O. Yakubovich (Russia) presented a polysomatic series of layered vanadates, arsenates and phosphates using the modular concept. X. Zou (Sweden) described new TEM techniques for solving three-dimensional structures of nanosized and/or intergrown zeolites and minerals.Chairs: Oleg Siidra and Biljana Lazic
The session on 'Heavy Crystals: Structural Crystallography of Heavy-element Compounds' (MS19) began with invited lectures on the crystal chemistry and physical properties of intermetallic compounds (E Gaudin, France), and the influence of 'lone-pair' cations (Pb2+, Tl+) on geometry and dimensionality of oxosalt inorganic compounds (O. Siidra, Russia).
Three selected speakers discussed structures and stabilities of LiCeF5 and LiThF5 at high pressures (A. Grzechnik, Germany), novel silicates with the apatite crystal structure (M. Wierzbicka-Wieczorek (Germany), and structural variety of novel Pb and Bi selenites (V. Kovrugin, France and Russia).The broad range of these talks provided a general overview of the crystal chemistry of heavy elements.Chairs: Olga Yakubovich and Marie Colmont
The session 'Aperiodic Crystals: Structure, Dynamics and Magnetism' (MS14) focused on new types of research on quasiperiodic systems, epitaxial order in quasicrystals, and incommensurate magnetic structures. V. Petříček (Czech Republic) described a new option in JANA2006 for the determination of commensurate and incommensurate magnetic structures combining representational analysis and magnetic symmetry. H. Sharma (UK) discussed the structure of ad-atoms on a five-fold surface of a quasicrystal where a quasiperiodic arrangement of Pb atoms is observed, in good agreement with preferential sites observed on the bare surface. Subsequently, H. Stokes (USA) presented new features of the program ISODISTORT, and showed that skyrmion-type spin configurations are simply obtained as incommensurate arrangements caused by the action of a single multi-k irreducible representation (see Figure). K. Christensen (UK) discussed the investigation of modulated molecular structures in a general service diffraction laboratory. R. David (France) described iron compounds that exhibit a complex interplay of commensurate and incommensurate structural and magnetic ordering.Chairs: J. Manuel Perez-Mato and Marc de Boissieu
In the session 'Crystallization and Crystal Treatment', D. Maes presented atomic force and laser confocal microscopy images of growing crystal surfaces showing the dramatic effect of these impurities, and how important it is to 'feed' crystals with pure protein. E. Garman, a.k.a. Auntie E, shared typical questions sent to her: 'I am in a polycrystalline relationship, and a loop has been hitting on me lately, how do I get out of this?' and 'I am experiencing embarrassing dryness and skins, what should I do?'. Auntie E gave wise advice to these crystals on how best to behave under stressful cryoconditions. J. Hasek showed how polyethylene glycol, polyethylene oxide type polymers, non-ionic detergents, and carboxylic acids could act as protein surface-active molecules. These 'sticky' molecules help form interactions on the protein surface that promote crystal contacts. Beamline scientist T. Kumasaka described the use of polyvinyl alcohol as a non-toxic sticky glue to stabilize the protein crystal under humidity control and subsequent cryocooling. Finally, T. Wagner presented GuideX, a database system to keep track of the 6000 or so small-ligand compounds that she manages at Novartis.Chairs: Jose Gavira and Terese Berfors
Teaching, Art, History
Two invited lectures in 'Crystallography in Art and Archaeology' (MS40) examined artworks from the ground up. P. Bezdicka (Czech Republic) described how the powder diffraction pattern of the ground used to line an entire canvas clearly distinguishes among the five main sources of clay, widely used in Central Europe between the 16th and 19th centuries.
A. Rafalska-Lasocha (Poland) then discussed powder diffraction analysis of the origin and aging of the paint layer as a guide to conservation of art works. From 1750 to 1850, Naples Yellow contained lead antimony oxide mixed with potassium lead sulphate. In the late 1800s the second component was changed to zinc oxide. Green pigments usually are made from copper compounds, which may degrade over time. The identity of yellow and white pigments in two portraits of King John III Sobieski, who drove the Turks from Vienna in 1683, suggested they could be by the same artist.
J. Rius (Spain), described transmission micro-diffraction experiments on polished thin sections with synchrotron radiation. Typical samples were 15-30 μm thick, mounted on 1 mm glass slides, yielding discrete patterns or Debye rings depending on the number of grains struck by the beam.
L. Holland (UK) described the 'Light Reading' short story competition, www.light-reading.org, conceived by Diamond staff to draw parallels between the creative and scientific processes. The Diamond synchrotron building, science or scientists were to be mentioned in the story. The first competition in 2011 attracted over 70 entries from adults from around the world; in 2012 the competition was for 12 to 16 year olds.
D. Viterbo (Italy) discussed crystallographic themes in the writings of Auschwitz survivor Primo Levi (1919-1987). Levi's 1980 book 'The Search for Roots: a Personal Anthology' includes sections inspired by W. H. Bragg's book 'Concerning the Nature of Things', which also sparked Dorothy Hodgkin's interest in crystallography.Chairs: Carl Schwalbe and Massimo Nespolo
In 'Crystallographic Teaching and Education' (MS41), crystallographers from France, Italy, Belgium, Spain and the UK described plans to celebrate the International Year of Crystallography. J.-L. Hodeau (France) described an exhibition called the 'Voyage dans le Crystal' (http://iycr2014.org/resource-materials/voyage-dans-le-cristal) that travels from prehistoric times to modern day, describing the beauty, mystery and modern applications of crystals.
L. Van Meervelt (Belgium) described a crystal-growing competition for high school students that has been held for the past 13 years in Belgium. Students grow crystals of alum and prizes are awarded at a public ceremony. In 2014 the contest will be open worldwide.
A. Warren (UK) gave a summary of the Big Bang Fair in London, where the Science and Technology Facilities Council, the BCA, Diamond, ISIS and YGG (Young Crystallographers Group) sponsored a Crystallography booth with hands-on experience for thousands of visitors. The YGG is very active in the dissemination of crystallographic science in Bristol (Kitchen Chemistry) and at Diamond Open Days. The audience was invited to build a unit cell with toothpicks and marshmallows.
The activities in Spain will include a crystal growth competition for students which began in Andalusia, Asturias, Catalonia and Aragon in 2008 and will extend to other regions in 2014. The programme 'Science, Crystals and Society' includes a short video showing 'What does a crystallographer do?', a 2014 'Crystallography diary and calendar' for 2014 (paper and virtual editions), a 'Postage Stamps exhibition' and a 'Virtual Geology Museum'.
M. Zema (Italy) described the long history of International Schools of Crystallography in Italy and announced the 'First European Crystallography School' supported by the ECA, which will be held in the IYCr 2014.Chairs: Annalisa Guerri and Elena Boldyreva
In a microsym. on 'The History of the ECA' (MS42), A. Authier (France) discussed the emergence of crystallographic groups in many European countries in the 20 years following the founding of the IUCr in 1948. In 1972, despite complicating political challenges, many of these national groups formed the European Crystallographic Committee (ECC). There is general agreement that Authier's efforts to form these make him the progenitor of the ECA.
H. Fuess (Germany) described the 'Transition from a Committee (ECC) to an Association (ECA)'. Crystallographic meetings of the ECC improved cooperation between European researchers and soon led to a more structured organization. In 1997, the ECA was founded. Fuess registered as IM (Individual Member), number 1.
Santiago Garcia-Granda (Spain), past-president of the ECA, described the growth in size, scope and accomplishments of the ECA. He presented an elaborate and elegant exposition about many things related to the growth in size, power and achievements of the ECA. His presentation is available at the ECA website.
Jan Boeyens (South Africa) described how crystallography was first established in South Africa (around 1937). Soon after the birth of the ECA, the IUCr created the concept of 'Regional Associates', and the ECA accepted the responsibility for Africa as part of the Euro-African Region to cultivate crystallography in Africa. Though partly successful in Northern Africa, much remains to be done in central Africa.
William Duax (USA) drew upon his large collection of photos taken at ECM meetings to review the people (portraits, committees, social gatherings) and events (scientific meetings, official ceremonies, excursions, gala dinners) of ECA's history. Most of the photos are stored in the collection that has been organized chronologically on the IUCr website, thanks to the efforts of the talented staff in Chester.Chairs: Sine Larsen and Paul Beurskens
The 29th Meeting of the European Crystallographic Association (ECM29) will be held in Rovinj, Croatia, August 23-28, 2015. Visit the website at http://ecm29.ecanews.org/.