Aligning crystals using X-ray Laue

Step 1

  • Check the correct sample position in Sample cells page, and put a mark at the sample position on the Al plate.

  • Dismount the Al plate from the holder.

  • Attach the sample on the Al plate using GE vanish or CYTOP. If you use GE vanish, the amount of the vanish should be minimized to reduce the incoherent background signals from hydrogen.

  • The sample should be attached on the rotation axis, that is the vertical dotted line shown in the figure (right or bottom).

Step 2

  • Mount the sample with the Al plate onto the sample holder, and measure a X-ray Laue diffraction pattern.

  • If there is a misalignment regarding the azimuthal angle psi, fix it by tilting the Al plate. (Loose the screws indicated by red arrows in the picture below, tilt the Al plate and tighten the screw.)

  • To simulate X-ray Laue diffraction patterns, a web simulation tool is available : X-ray Laue backscattering pattern simulator

Step 3

  • If there is a misalignment regarding χ direction, fix it by bending the Al plate.

  • The misalignment regarding ψ and χ should be less than 2 degrees.