Round robin study : X-ray Diffraction of LaB6 Standard Reference Material

As a Characterization@UBC research excellence cluster activity, this inter-laboratory round-robin study benchmarked powder X-ray diffraction (XRD) performance using NIST Standard Reference Material 660a (LaB6). Six diffractometer configurations across three facilities were compared and evaluated, within the Electron Microscopy Laboratory (EM Lab), the Electron Microscopy and X-ray Diffraction Facility (EMXDF), and the Department of Chemistry. For each instrument, peak positions relative to the certified reference values were compared to confirm instrument accuracy, and instrumental peak broadening was quantified using the full width at half maximum (FWHM) and the Caglioti function parameters were determined to compare the instrumental resolution functions. During the first phase of the study, one diffractometer configuration (MTRL D6 with the original Universal stage, Uni-Old) exhibited a systematic angular offset of about 0.13°, despite the instrument having been commissioned only a couple of years ago. The phase one data indicated that this specific instrument had a hardware issue, which was unknown to the instrument users. The findings were communicated to the instrument manufacturer, and this resulted in replacement of the Universal stage (under warranty). The LaB6 measurements were subsequently repeated using the replacement stage (Uni-New), demonstrating substantial improvement in both peak position accuracy and peak-width behavior, and now the instrument is in agreement with the performance of the other participating facilities (and the documentation associated with the standard). Beyond comparing instruments, the study demonstrates how cross-facility benchmarking can serve as an effective quality-assurance process by detecting hidden faults, verifying corrective maintenance, and generating reference data for future performance checks. We encourage XRD facilities across UBC to use comparable standard reference material-based measurements routinely, particularly after major service, optics changes, or suspected instrument drift. This round-robin exercise also provided an opportunity to build community, share know-how, and highlight the benefits of working together across the UBC research environment towards an improved understanding of characterization technologies. This work advances Characterization@UBC’s goals of connecting complementary facilities, sharing technical expertise, and strengthening shared research infrastructure. The resulting common benchmark and repeatable quality assurance workflow support more consistent user service and greater confidence in XRD data produced across UBC.