Tellurite And Fluorotellurite Glasses For Active And Passive

5. Crystallisation studies; MDO 135
Aluminium
plate
Interpretation of powder patterns
Fig. (5.1): XRD sample holder.
In this study, Bruker software was used to label peaks, and identify (if any) crystalline
phases present in the sample. This software labels peaks on the trace with their
corresponding d-spacings. A CD-ROM database of diffraction patterns from the Joint
Committee on Powder Diffraction Standards (JCPDS) was searched for each trace. The
elements thought to be present in the powdered sample were entered in to the software,
which finds all patterns available with any combination of these elements. These patterns
can be compared with the recorded trace, enabling the identification of the composition
and structure of the powdered sample. Usually, the three or four most intense peaks are
used to identify unknown crystals, as no two crystalline materials have identical d-
spacings and relative intensities [1].
5.1.1.2. Theory of operation
≈ 2.5 cm
Sample
Perspex
block
The structure of a crystal can be identified using radiation of a wavelength comparable to
the interplanar spacings in the material. The interplaner spacings in most crystals are in