Thin-foil samples for Stoe diffractometer with Mo X-rays

Thin-foil samples for Stoe diffractometer with Mo X-rays

Remove two pre-cut cellulose triacetate foil from the container using very clean fingers (and definitely no gloves) as the supply of foils must not be contaminated with extraneous material). Note that the foils as supplied tend to stick together so check that you only have taken two (per PXRD sample to be prepared) by rubbing gently between your finger and thumb.

Very lightly grease one side of the foil with silicone grease and put a small amount of sample in the centre (aim for a small pile about 8 mm across). Use of too much grease will result in large broad peak appearing at lowish angle in the PXRD pattern. Then sandwich the sample with the second ungreased foil as shown below:

Gently loosen the screws with a jewellers screwdriver on the foil sample holder (do not remove the screws completely as they are easily lost) and remove the clamping metal aperture as shown below:

Note that the metal apertures come in two sizes. The one in these photos is a small 4 mm diameter aperture one for use with tiny samples. In general, it is better to prepare enough sample material so that the larger 8 mm diameter hole apertures can be used.

Carefully place the sandwiched sample in the middle of the sample holder as shown below:

Now gently place the metal aperture on top and rotate so that the edge slides under the screw heads. The screws can then be finger tightened so that the metal aperture plate does not fall out of the holder. No force is required to tighten the screws!

N.B. Do not be tempted to use other tools to loosen or tighten the screws as the head and threads are easily damaged.

PXRD Material Index

Author(s): Jeremy Karl Cockcroft
Martin Vickers