Anomalous extinction of X-rays diffracted in strongly deformed crystals

The extinction concept is extended for very thin non-ideal crystals. It is shown that for a large gradient, the integrated reflected intensity exhibits a prominent extinction minimum. This anomaly is an interbranch effect, occurring for crystals with thicknesses of the order of the interbranch extinction length. Different possibilities for applying this newly developed extinction theory to X-ray integrated wave topography are discussed.