School and Conference on Analysis of Diffraction Data in Real Space
Co-organised by:
The European Synchrotron (ESRF)
and the Institut Laue-Langevin (ILL)
Conference poster now available here.
Aim, Scope and Format
The ADD2026 School and Conference aim to deepen the understanding and to further the training of the various communities working with real-space data analysis methods in neutron and x-ray diffraction. The Fourier transformation of total-scattering diffraction data from reciprocal space into real space produces a Pair-Distribution Function (PDF) that represents a model-independent "snapshot" of the short-range atomic structure within the sample. The PDF(r) thus probes both static and dynamic local atomic correlations (as well as local magnetic spin correlations in the case of neutron diffraction). The measured PDF(r) can then be modelled or simulated using various software packages. These so-called "PDF-analysis" methods are therefore complementary to the well-known Rietveld method of refining diffraction data in Q-space that however provides a space-time averaged picture of the structure.
Although originally used to determine the short-range atomic order in liquids and glasses, PDF analysis of total-scattering diffraction data is increasingly applied to powder samples of partially disordered crystals and a variety of nano-structured systems, as well as to single-crystal samples exhibiting some local atomic disorder, and for short-range spin correlations in disordered or frustrated magnetic systems (in the case of neutron diffraction). Consequently, PDF-analysis enjoys a wide field of application to new functional materials, whose properties often depend significantly on their local structure rather than only on their average crystallographic structure.
The scope of ADD2026 responds to this growth in PDF-analysis applications by covering both x-ray and neutron diffraction techniques that involve real-space modelling/analysis of local atomic and/or local magnetic structural correlations for samples of any morphology. Note that we also welcome presentations and participants in the field of e-beam diffraction using real-space analysis techniques.
The 5-day programme of ADD2026 builds on the success of our five previous ADD workshops in Grenoble: ADD2022 of 16-21 October 2022, ADD2019 of 17-22 March 2019, ADD2016 of 7-11 March 2016, ADD2013 of 18-22 March 2013, and ADD2011 of 12-14 October 2011. The ADD2026 School+Conference will start Sunday evening 11 January 2026 and finish Friday afternoon 16 January, which includes 2-1/2 days for the School followed by 2-1/2 days for the Conference, basically the same format as for ADD2019 and ADD2022.
The ADD2026 School proposes pedagogic lectures on real-space data-analysis techniques followed by a choice of 2 among 10 different hands-on tutorials for training with various data-modelling software packages: DiffPy-CMI, diffpy.mpdf, DISCUS, EPSR+Dissolve, PDFgui, RMCProfile, Spinvert, Spinteract, Topas and Yell. The ADD2026 Conference proposes 8 invited talks and 17 oral contributions, as well as a poster session.
Other than the lectures and tutorials on modelling and simulation techniques, the ADD2026 School also features short lectures on nitty-gritty data-reduction and data-correction methods for x-ray and neutron diffraction as concerns liquids/glasses, disordered crystals and single-crystal diffuse scattering.
Real-space analysis of diffraction data deals with general structural concepts such as atomic/spin distribution functions and structural/magnetic correlation lengths, and employs standard formulas common to neutron, x-ray and other diffraction techniques. It therefore facilitates the convergence of hitherto disjoint communities: liquids/glasses diffraction, crystalline powder diffraction, single-crystal diffuse scattering and diffuse magnetic scattering.
