Tellurite And Fluorotellurite Glasses For Active And Passive

5. Crystallisation studies; MDO 138
and
E M = d sinθ
(5.3)
2
2
1
E N = d sinθ
(5.4)
2
Hence, the total path difference equals 2dsinθ which should be integral multiples of λ:
n λ = 2d sinθ
(5.5)
This is known as the Bragg equation.
The powder diffractometer
Originally powder-XRD was performed using the powder photographic method, where
the whole diffraction pattern is recorded simultaneously on a photographic film. This
method was tedious as the film had to be exposed to the X-ray beam for long times, and
there were problems associated with developing the film [1]. This has been overcome by
the powder diffractometer technique. The diffractometer has the advantage of higher
resolution by recording small ranges of 2θ on an expanded scale. The diffraction pattern
is scanned by a counter device (Geiger proportional or scintillation counter) or a solid