Vibration is the key to moving the sample down and a good light source behind the capillary is needed to see whether the sample has moved down the capillary and/or is coating the sides of the capillary. Load only the smallest amount (<1 mm deep) of material into the capillary funnel at any one time - otherwise the sample becomes stuck pretty early on in the capillary.
The sample should be finely and uniformly ground Hints for loading capillaries are as follows: For non-standard thicker-walled quartz capillaries, users will need to contact Hilgenberg directly for pricing and availability. Where can I purchase suitable capillaries?Ĭapillaries can be purchased from Charles Supper or Hilgenberg and will take at least two weeks to be delivered (for standard stock items). Most low- or ambient-temperature experiments will use 'special glass' or 'borosilicate' capillaries', but high-temperature experiments will require 'quartz' capillaries (these can be used up to 1370 K).Ĥ. Photographs showing the distance between the goniometer head to the edge of the X-ray beam for short samples (left) and for long samples (right).ģ. To seal the capillary break off the funnel, and any excess capillary, and seal it at least 10 mm away from the sample.įigure 1. NOTE: samples prepared for use in conjunction with the cryostream and hot-air blowers must be long. The location of the beam on the sample using the two sample mounting options available is shown in Figure 1. However, if only a small amount of sample is available it is possible to work with as little as 3-5 mm of sample, if care is taken when positioning the sample.
Capillary sizes >0.5 mm are not recommended.įor ease of experiment set-up, the length of sample needed in the capillary is usually 15-20 mm (or more), above the brass stub holding the capillary. It is normally recommended that users use 0.3 mm low X-ray absorption glass capillaries the angular resolution is optimised by using as small a diameter as possible. This section describes how this can be done. Where possible, samples should be loaded in capillaries for data collection.
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