Standards Data

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starting May 2013, data are moved here from the 11BM webpage (http://11bm.xray.aps.anl.gov/standards_data.html)

Standard Reference Materials

Details of powder diffraction data measured at 11-BM for standard reference materials are listed below and are available in several formats. These are periodically updated. Contact 11-BM staff with questions.

Data are typically measured at ~ 30 keV under ambient conditions. Check the file header for full details and scan parameters.

More information about 11-BM data collection and data formats can be found here:

NIST SRM Certificates (with lattice values etc) are available for download here:

Lanthanum Hexaboride (LaB6), NIST SRM 660a

Rietveld Fitting LaB6

Silicon (Si), NIST SRM 640c

Empty 11-BM Kapton sample capillary

11-BM background, air scatter only (no sample)

Note: exact background shape for 2θ < 2° may vary due to beamstop positioning. Contact 11-BM staff with questions.

NAC (Na2Ca3Al2F14)

Rietveld Fitting NAC

Instrument Parameter and Input Files

GSAS

On-site and Mail-in users requesting GSAS format data will receive an appropriate .prm parameter file with their data.

When using the example .prm files with SRM data above, manually modify the wavelength in the .prm file as needed.

TOPAS

11-BM data can be obtained in a TOPAS (.xye) format compatible with both professional and academic versions of the software.

TOPAS does not use an instrument parameter file like GSAS and FullProf, instead it has instrumental parameters nested within the .INP file.

The TOPAS .inp file below uses the "simple axial model" (combining a pseudo-Voigt profile with an axial divergence asymmetry correction) to fit an example LaB6 660a dataset collected at 11-BM.

The .inp file provided here is meant for TOPAS in launch mode. If you are attempting to load it in project mode, it will not work. To load it in launch mode, click on Launch then Launch Kernal. Afterwards set the inp file with the corresponding menu option. If you want to see what the inp file is doing, you can open it in any text editor.

Note #2: this is only one example of a TOPAS profile fit using the Simple_Axial_Model; your data may be best fit by an alternative profile. For details consult the .inp file and other TOPAS resources, this example kindly provided by Dr. Saul Lapidus at Argonne National Laboratory

FullProf

11-BM data can be obtained in a Fullprof (.xy) INSTRM=10 format. However, we do not provide supporting .prc or .irf files.

11-BM users may find the example files below useful when starting a FullProf refinement.

Note: based on a refinement of LaB6 660a data; 2010-1 cycle (30 keV), kindly provided by Dr. Joel Reid at the International Centre for Diffraction Data



Please contact beamline staff if you have 11-BM instrument parameter files for other refinement software packages that you'd like to share with our users - we'd be happy to post it here. Fits using the above standard reference data would be particularly welcome