A simple white beam neutron diffraction technique

Abstract

White beam neutron diffraction by time-of-flight (TOF) technique has been studied over a number of years as it is believed to be the most convenient method to investigate solids in a fixed geometry. This technique needs a pulsed neutron source and a suitable multichannel, analysing system. The entire system is in general, mechanically quite intricate and expensive.

We have investigated an alternative technique to achieve the end result of a constant geometry around the diffracting sample. This involves the use of a single crystal as an analyser to study diffraction pattern from the sample bathed in a white beam and diffracting at any fixed scattering angle. In this paper we report the results of our investigations and have compared this technique with other diffraction techniques. Taking Si, KCl and KNO₃ as typical specimens we have illus. trated the results of our technique and we find that the results are comparable to those obtained by conventional neutron diffraction and TOF diffraction. The technique is simple in mechanical design and data acquisition. It can be easily adapted for high pressure diffraction which is being attempted.