Tellurite And Fluorotellurite Glasses For Active And Passive

5. Crystallisation studies; MDO 134
5. Crystallisation studies
The aims of this chapter are: to use X-ray diffraction (XRD) to assist the monitoring and
optimisation of the purification procedures for glass batch precursors; to use knowledge
of the crystal structures of precursors materials to gain further insight into the structure of
tellurite and fluorotellurite glasses; and to use XRD to investigate the nature of crystalline
phases formed in devitrification of glasses during processing and characterisation.
5.1. Experimental
5.1.1. X-ray diffraction (XRD)
5.1.1.1. Method and instrumentation
X-ray diffraction (XRD) was performed in this study using a Siemens D500 powder
diffractometer. All traces were recorded using CuKα radiation at 1.5418 Å, scanning from
10 to 100° 2θ with a step size of 0.02° 2θ every 1 s (i.e. each trace took 75 min. to run),
at ambient temperature, in air. Samples were ground to a fine powder using a pestle and
mortar, and mounted in a Perspex / aluminium sample holder by compacting the powder
into a circular disc (1 to 2 mm thick) with a glass slide. Fig. (5.1) illustrates this holder.