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The first edition of the ECA European Crystallography School (ECS1), to be held in Pavia (Italy) during the course of IYCr2014, has found good balance between two apparently diverging goals: (i) to help students and young researchers to find their way in modern science, while keeping a special focus on the molecular and crystalline structure to interpret properties and functionality of materials; (ii) to raise the social and academic awareness of the great advances that crystallography has allowed and will allow to many branches of sciences. Students may choose between two formulae, i.e. a 6-day course with lectures and hands-on sessions held by renowned scientists, covering the state-of-the-art of crystallographic methods, theories and applications, at the same time indicating their future perspectives and cutting-edge aspects, or a 10-day Erasmus Intensive Programme, including a 3-day preparatory course and granting 3 ECTS credits. IYCr2014 is a unique opportunity to stimulate and ignite widespread interest in crystallography; therefore, some frontier seminars will be open to University faculty members, students, and to the general public. Efforts will be made to create a nice and friendly environment, with the goal to provide chances for future collaborations. Students will be invited to bring a poster showing their research results, projects or scientific interests. This will allow students to discuss their ideas with experienced crystallographers and favour aggregation. The programme received good support from scientific institutions and vendors, and a great response from the students: more than 110 pre-registrations from 33 countries were already received at the time this abstract was prepared, showing that there is a real need for both fundamental and advanced teaching in crystallography. We hope that this format will be continued and improved so as to provide a stable, periodic rendezvous for students and researchers under the common theme of crystallography.
abstracts
The mechanism of a solid state reaction in its early stages can be explored by investigating the time evolution of a model reactive system made of a thin layer of one reagent deposited onto a single crystal slab of the other reagent. Insights can be retrieved by comparing results at both local and long length scales obtained with films of different thicknesses and deposited onto different crystal orientations. In particular, reaction between ZnO and Al2O3 has been chosen, as the spinel-forming reactions have been and still remain a model experimental system for investigating solid state reactions and because in the ZnO/Al2O3 phase diagram, spinel is the only stable compound. The reaction initial steps have been investigated by using synchrotron X-ray diffraction, atomic force microscopy and X-ray absorption spectroscopy at the Zn-K edge starting from zincite films deposited onto (110)-, (012)-, (001)-oriented corundum single crystals [1,2]. The reaction eventually yields ZnAl2O4 spinel but via a complex mechanism involving side and intermediate non-equilibrium compounds that do not appear in the equilibrium phase diagram of the pseudo-binary system. Spinel, when occurs, is polycrystalline at the end but initially forms with a few preferred orientations. Intermediate phases form before and in parallel with the growth of the spinel. Their number, composition, structure and kinetic role strongly depend on substrate orientation and film thickness. A more detailed understanding of the reactivity can be inferred by comparing EXAFS results to those of grazing incidence diffraction experiments of the films deposited on the (001) face of Al2O3 and heat-treated at 1000 0C for different lengths of time. Information on the structure of the intermediate phases is given and results are discussed by comparing different films thickness to clarify the role of interfacial free energy and crystallographic orientation.
