A simple model for dynamical neutron diffraction by deformed crystals

A simple physical model is presented to predict the neutron diffraction properties of deformed crystals. The main interest of this model is its general applicability to deformed crystals and its mathematical simplicity. At first this model was applied to curved crystals and its validity was checked by comparison with the diffraction patterns obtained from the exact solution of the dynamical neutron diffraction theory. A comparison between the prediction of the model and experimental data in curved Si crystals is presented. Finally the model is used to predict neutron diffraction patterns by crystals with a gradient in the lattice spacing and by deformed crystals in the general case.