Standards Data

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NIST 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) - SRM 660a

NIST SRM 660a data

Rietveld Fit LaB6 660a

Lanthanum Hexaboride (LaB6) - SRM 660b

SRM 660b is the NEW reference material for LaB6 from NIST see Powder Diffraction, Volume 26, Issue 02, pp 155-158

NIST SRM 660b data

Rietveld Fit LaB6 660b

Silicon (Si), NIST SRM 640c

Silicon (Si), NIST SRM 640d

11-BM data for 640d

Rietveld fit for 640d

Aluminium Oxide (Al2O3), NIST SRM 676a

NIST SRM 676a consists of an alumina powder (corundum structure) intended primarily for use as an internal standard for quantitative analysis and I/Ic. It is *not* the primary SRM for lattice and peak profile analysis (use Si or LaB6 instead)

11-BM data for 676a

Rietveld fit for 676a

NIST SRM 674b

Standard Reference Material 674b consists of four oxide powders to be used as internal standards for qualitative X-ray diffraction analysis. See the NIST reference sheets for more information.

ZnO powder for 674b

11-BM data

Rietveld fit

TiO2 674b

Data for the TiO2 powder sample of SRM 674b measured at 11-BM was determined to be poorly crystalline and not phase pure (less than 90% crystalline phase pure even according to the SRM), and contained a mix of Anatase and Rutile TiO2 crystalline forms. Therefore, it is not considered a useful SRM sample for 11-BM users and the data are not provided here. Ask 11-BM staff if you have a particular interest in TiO2 as an SRM.

Cr2O3 powder for 674b

11-BM data

Rietveld fit

CeO2 powder for 674b

11-BM data

Rietveld fit

Other Reference Materials

NAC (Na2Ca3Al2F14)

Na2Ca3Al2F14 (NAC) is not a official SRM from NIST, but can be used as a low Z sharp line profile standard with strong peaks at lower 2theta (compared to LaB6). See J. of Solid State Chem. 76, 2, 1988, pp 426–431

11-BM data for NAC
Rietveld Fitting NAC

Empty 11-BM Kapton sample capillary

Background at 11-BM, air scatter only (no sample)

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

Mounting Red Clay used at 11-BM

Data for the red modeling clay (plasticine?) often used at the 11-BM beamline to seal Kapton capillaries

Metal from 11-BM Mail-In Sample Base

If the Robot Z-stage position is positioned incorrectly, the 11-BM beam might diffract from the metal sample mounting base. (We assume the material aluminum?). This data is given as a reference only in case one suspects the sample was positioned incorrectly in the beam.

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.

Important : 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 : 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

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