Neutron Powder Diffraction Tools

The RWTH Aachen university group is dedicated to advancing neutron time-of-flight (TOF) powder diffraction methods, particularly in relation to the POWTEX diffractometer [1] and the DAPHNE project (UC8). Both projects aim to extend the developed methodologies across suitable TOF diffractometers. Key tasks include multidimensional data reduction utilizing the Mantid software [2], incorporating fundamental instrument descriptions into NeXuS files, and enhancing Rietveld refinement techniques. Recent results, e.g. on multidimensional Rietveld refinements of high-pressure neutron TOF powder diffraction data from SNAP at ORNL [3-6], have successfully demonstrated the methods. To streamline data analysis, a centralized nexus file has been proposed to consolidate essential instrument-specific metadata, thereby enhancing efficiency and supporting sustainability by ensuring that necessary information is readily available during data reduction processes. Complementing these efforts, AIXtal serves as an innovative refinement platform tailored for first-time users also developed within the DAPHNE project. It features a simplified interface with tutorials, tooltips, and AI helpers designed to assist in refining powder X-ray diffraction data using GSAS-II [7] and Fullprof [8]. AIXtal's functionalities include visualization of structural and experimental data, on-demand assistance for refinement parameters, and the ability to export results in GPX format. Currently in alpha testing with chemistry students, AIXtal v2 is under development to enhance usability through multiple operation modes and improved performance using the Rust language to compile WebAssembly or cross-platform executables. This version aims not only to support multidimensional data sets but also introduces an expert mode for advanced users. The integration of AI tools [9] within AIXtal will further facilitate structure solution and profile refinement for users of all experience levels, ultimately broadening the applicability of these advanced crystallographic methods across diverse platforms while aligning with the group's overarching goal of sustainable research practices.