It is shown in this paper that a feature that has been observed in the diff
use scattering patterns of a wide variety of different materials - a diffus
e 'ring' or 'doughnut'-shaped region of scattering - can be understood in t
erms of a simple model that has been borrowed from the field of sol-gel sci
ence. In this, it is supposed that there is a balance between the local att
ractive forces that are trying to make a particular structure and a rather
longer range repulsive force. In the present context, it is believed that t
his latter force has its origin in the strain that builds as the preferred
local structure tries to rt into the average crystal lattice. Simple Monte
Carlo (MC) computer simulations are described that demonstrate this princip
le for three example materials: cubic stabilized zirconia, the p-didecylben
zene/urea inclusion compound and the pure molecular compound 1,3-dibromo-2,
5-diethyl-4,6-dimethylbenzene, C12H16Br2 (BEMB2).