Diffraction studies of glass structure. I. Theory and quasi-crystalline model

Abstract A unified outline of the theory of X-ray and neutron scattering from glasses is presented, starting from the formalism of Van Hove. The nature of the structural information obtainable from scattering experiments is discussed and it is emphasized that the experimental data are usually inadequate for a full determination of the structure. It is necessary to use some kind of model in attempting to overcome this problem and a simple quasi-crystalline model is described. The use of this model is illustrated by considering its application to a range of simple disordered structures which are known exactly, namely computer-generated random sphere packings.