Abstract

A general theory for diffuse X-ray scattering from self interstitials in a lattice containing more than one atom per unit cell is presented. Expressions for Laue scattering at the defect and the scattering from the strongly distorted region around the defect are unaffected by the number of atoms in the unit cell. However, the larger diffuse scattering contribution from terms linear in the lattice distortions depend on the number of atoms in the unit cell. The general expression is calculated using a lattice statics technique. An expression is also given for the Huang diffuse scattering in a general lattice using the continuum theory of linear elasticity. As an example, Huang diffuse scattering calculated from the lattice statics method and elasticity theory is compared in zinc, an h.c.p. lattice with two atoms per unit cell.