Additions/Corrections/Changes Welcome
The problem and possible solutionCalibration is necessary for PSD (Position Sensitive Detectors) based instruments to relate channel number to two-theta angle. This is especially so with INEL PSDs where there can be discontinuities not modellable via normal polynomial fitting. (instead use a spline curve fit where the curve has to go through each calibration point). Hoever a common problem is that most standards do not have many peaks at low angle. Thus Silver Behenate (c-axis= 58.373 to 58.380 Anstrom) for low to medium angle calibration; combined with an appropriate medium to high angle standard (such as Cubic Y2O3 (IA3 a=b=c=~10.6 Angstrom) - annealed at 1200°C for a few days) may offer a solution covering the entire angular range. The following is based around the following publications and data:
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Obtaining Silver BehenateQuoting from Blanton, et al (2000), "Eastman Kodak Company provided silver behenate to The Gem Dugout (Smith. 1999). from where it may be purchased for scientific study. One-half of the purchase price is donated to the International Centre for Diffraction Data for the ICDD Crystallographic Scholarship fund.]" Smith, D.K. (1999). The Gen Dugout. 1652 Princeton Drive, State College, Pennsylvania, 16803, USA. E-mail: smithdeane@aol.com
Other Available NIST/NBS XRD Standards
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Data and Tutorial Run Throughs
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