A N.M.R. spectrometer for Knight shift investigations.

Abstract

This thesis describes the design, assembly, operation and behaviour of a nuclear magnetic resonance spectrometer of the Pound-Knight type built for investigation of Knight shift in metals and alloys. A brief introduction to nuclear magnetic resonance is given followed by a short discussion of the Knight shift. A short description of the various arrangements for observing nuclear magnetic resonance is given and after pointing out the requirements for observing the Knight shift in metals, our choice of the spectrometer is justified. The working of the spectrometer as a whole unit is explained and this is followed by a description of its various components. The technique of determining frequency is described in detail by giving a typical example of A127 signal from a solution of AlCl3. The behaviour of the spectrometer is discussed and its use in detection of various signals is given. The necessary conditions for obtaining good signals are summarised. The temperature variation and also the homogeneity of the magnetic field are studied with the aid of the spectrometer. The accuracy and usefulness of the equipment is tested by measuring the Knight shift in aluminium metal.