title: Raw diffraction data preservation and reuse: overview, update on practicalities and metadata requirements.
abstract: A topical review is presented of the rapidly developing interest in and storage options for the preservation and reuse of raw data within the scientific domain of the IUCr and its Commissions, each of which operates within a great diversity of instrumentation. A résumé is included of the case for raw diffraction data deposition. An overall context is set by highlighting the initiatives of science policy makers towards an 'Open Science' model within which crystallographers will increasingly work in the future; this will bring new funding opportunities but also new codes of procedure within open science frameworks. Skills education and training for crystallographers will need to be expanded. Overall, there are now the means and the organization for the preservation of raw crystallographic diffraction dataviadifferent types of archive, such as at universities, discipline-specific repositories (Integrated Resource for Reproducibility in Macromol-ecular Crystallography, Structural Biology Data Grid), general public data repositories (Zenodo, ResearchGate) and centralized neutron and X-ray facilities. Formulation of improved metadata descriptors for the raw data types of each of the IUCr Commissions is in progress; some detailed examples are provided. A number of specific case studies are presented, including an example research thread that provides complete open access to raw data.
authors.affiliation: Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, Utrecht, CH 3584, The Netherlands.
authors.forename: Loes M J
authors.initials: LM
authors.lastname: Kroon-Batenburg
authors.affiliation: School of Chemistry, Faculty of Engineering and Physical Sciences, University of Manchester, Brunswick Street, Manchester M13 9PL, UK.
authors.forename: John R
authors.identifier: https://orcid.org/0000-0002-0520-7540
authors.initials: JR
authors.lastname: Helliwell
authors.affiliation: International Union of Crystallography, 5 Abbey Square, Chester CH1 2HU, UK.
authors.forename: Brian
authors.identifier: https://orcid.org/0000-0003-0391-0002
authors.initials: B
authors.lastname: McMahon
authors.affiliation: Bioscience Division, Los Alamos National Laboratory, Mail Stop M888, Los Alamos, NM 87507, USA.
authors.forename: Thomas C
authors.identifier: https://orcid.org/0000-0001-6384-0320
authors.initials: TC
authors.lastname: Terwilliger
keywords: data archiving; diversity of crystallographic instrumentation; metadata descriptors for raw data; raw diffraction data