Theory and applications of x-ray standing waves in real crystals

Theoretical aspects of the x-ray standing wave (XSW) method applied for inv estigation of real structure of crystals are considered in this review pape r. Starting from the general approach of secondary radiation yield from def ormed crystals, this theory is applied to different concrete cases. Various models of deformed crystals, such as the bicrystal model, the multilayer m odel and crystals with an extended deformation field are considered in deta il. Specific features of XSW behaviour in different scattering geometries ( Bragg, Laue) are analysed in detail. New approaches to solve the phase prob lem using the XSW method are also discussed. General theoretical approaches are illustrated with numerous experimental results.