11BM Calibration Sample: Lattice & Atomic Position Values

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Calibration of the wavelength at 11-BM is performed using a mixture of NIST standard reference materials (SRMs).

As of 2011, the calibration sample is a mixture of ~ 70 wt% Si (SRM 640d) and ~ 30 wt% Al2O3 (SRM 676).

Lattice & Atomic Position Values are as follows:

Si (SRM 640d)
Space Group: F d -3 m
Lattice: 5.431590 5.431590 5.431590  90.0000 90.0000 90.0000
Atom1: Si @ x = 1/8, y = 1/8, z = 1/8


Al2O3 (SRM 676a)
Space Group: R -3 c
Lattice: 4.7590914 4.7590914 12.991779  90.0000 90.0000 120.0000
Atom1: Al @ x = 0, y = 0, z = 0.351869
Atom2: O @ x = 0.307804, y = 0, z = 1/4

As of 13 February 2013, we started using the revised certification for 640d, for which the parameters are

Si (SRM 640d)
Space Group: F d -3 m
Lattice: 5.431230 5.431230 5.431230  90.0000 90.0000 90.0000
Atom1: Si @ x = 1/8, y = 1/8, z = 1/8