Third generation synchrotron have renewed the possibilities to use topographic settings for the study of materials, hence the necessity of versatile simulation programs to characterize their intrinsic quality.

A new generation of programs, based on the integration of Takagi-Taupin equations, has been designed on the principles of TRANSQ [1]: the computation of the deformation is made in a separate program allowing to easily change the model without modifying the simulation program. The optical characteristics of the source are correctly taken into consideration, assuming either an incident coherent plane wave or a distribution of incoherent point sources along the surface of the crystal in the case of white beam topographs[2].

The suite is made of TRANSQ (white beam topography in the Laue case), TOPLANE (plane wave Laue topography), TOPRC (computation of rocking curves in the Laue case), REFPLANE (plane wave Bragg topography), REFRC (computation of rocking curves in the Bragg case). This later has been especially designed to study epitaxial thin layers taking into consideration both the deformation between the epilayer and the substrate and the differences in the structure factors of both parts.

Examples of applications will be shown: stroboscopic images of piezoelectric materials, 3D defects in quasicrystals, influence of the heat load at ESRF and of the curvature of the sample on the rocking curve profile.

[1] Y.Epelboin, J. Appl. Cryst. 29 (1996) 331-340
[2] V.Mocella, Y.Epelboin & J-P.Guigay, submitted to Acta Cryst.

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