Structural Characterization

Structural Characterization Beamline Advisory Group

The Structural Characterization BAG advises the MPE/SS group leaders and APS management on instruments and infrastructure related to structural determination techniques used at 1-BM, 11-BM and at 1-ID. This work is mostly crystallographic structure determination from powder diffraction, but also covers some micro-PDF work, primarily in diamond-anvil pressure cells and some diffuse scattering work. The membership of this committee can be found on the appropriate XSD web page.

August 2009: Phase-II 1-ID upgrade

A short outline/justification (view here) for the proposed Phase-II upgrade of 1-ID was sent to Structural Characterization BAG on Aug 5 (view e-mail). The chair, Angus Wilkinson, stated in response "I am certainly in favor of the proposed construction of a new hutc h so that each of the major programs at 1-ID can have dedicated space and keep their setups in place and optimized. There will clearly be benefits for all of the high energy programs at 1-ID. Repeatedly tearing down setups and rebuilding them is a waste of time and leads to less than optimal experiments." This upgrade is more in the domain of the High Energy Materials Diffraction BAG, which sent a memo of support to the APS (view memo).

July 2009: Beamline newsletter

A update report was sent to the SC BAG describing news with respect to staffing, beamline upgrades and equipment purchases primarily on 11-BM (view newsletter).

April 2009: BAG Report

As a follow-up to the SC BAG meeting in March, the BAG wrote a report (view report). This noted with pleasure the performance of the beamline at higher energies (~30 keV) and the engineering and operation of the mail-in diffraction service. Priorities for development were recommended:

• publicize and expand the mail-in program
• purchase a replacement monochromator bender and crystal
• increase the range of accessible temperatures first below 80K and second above 500 K
• develop an on-site instrument control interface and then an on-site user program for 11-BM
• develop a on-site rapid data collection (area detector) program for materials powder diffraction; augmenting the capabilities of 1-BM would be ideal
• improve energy-change capabilities and extend the usable energy range, but this is of lower priority than the above topics.

March 2009: BAG meeting & Beamline newsletter

The SC BAG was provided with a summary of accomplishments, work in progress and future tasks (to be prioritized) for 11-BM (view document). On March 17, a meeting of the SC BAG was held with the 11-BM beamline staff and the BAG was asked to help set priorities for future work (a separate meeting was held with one BAG member on March 12 who could not attend March 17). A presentation was at the meeting on tests and problems encountered with energy changes on 11-BM (view slides). This shows why operation much below 15 keV is not possible at present.