HRPD Xpress is a new neutron powder diffraction measurement-by-courier service designed to provide quick access to high resolution neutron powder diffraction data.
HRPD Xpress beam time at ISIS is suitable for:
• new and infrequent users who may wish to test the feasibility of an experiment on HRPD before submitting a full proposal • PhD students who require urgently a limited amount of additional data in order to complete their thesis • research programmes requiring limited and/or occasional neutron beam time or those where multiple comparatively routine high-resolution neutron powder datasets are required
Typically, one day per cycle will be allocated to the Xpress service on HRPD. It is expected that the majority of this time would be devoted to room-temperature measurements using a dedicated sample changer. Where a compelling case for low-temperature is presented, then time may be made available for measurements at 10 K only in a CCR.
Peer-reviewed proposals will always take precedence over Xpress time in the instrument schedule and we cannot guarantee that the Xpress service will run at any particular time. However, we will make every effort to complete your measurements in the two cycles following submission.
HRPD Xpress will use standard vanadium cans of 8 mm diameter.
Please send your samples to the HRPD Xpress responsible (Dr Dominic Fortes, firstname.lastname@example.org). Users who prefer to load their own samples (e.g. air-sensitive or toxic samples) may request sample cans, which we will deliver to you. These should be filled to a height of approximately 20 mm (HRPD’s vertical beam height). In the event of self-loaded samples, users must include details of sample stoichiometry, mass and fill depth in order for us to accurately carry out an absorption correction.
All measurements will be made only in the instrument’s standard 30-130 millisecond time-of-flight window. Counting times will be at our discretion but we will endeavour to provide the best counted data that is commensurate with the time available.
After the experiment, the samples or sample cans will be returned to you (depending on the level of induced activity) so that you may recover your sample. You are then responsible for sending the empty cans back to ISIS.
Data will be collected in HRPD’s backscattering, 90° and low-angle banks, normalised and corrected for absorption using Mantid, and then emailed to you in a format suitable for Rietveld refinement, together with appropriate instrument parameter files (IPF). Users are expected to carry out the structural analysis with minimal assistance.
HRPD Xpress Access is not intended to provide a means of avoiding the usual peer-review process associated with Direct Access or Rapid Access and neither is it a substitute for good laboratory characterization of samples. For this reason, the Instrument Team reserve the right to cap excessive usage and direct users to send additional proposals via the normal FAP1 route.
Data collected using HRPD Xpress are subject to the normal ISIS policy regarding publication of scientific results, and bibliometric criteria, among others, will be used to assess the productivity of the scheme.