| Popis: |
A novel diffraction data integration method is presented,EVAL15, based uponab initiocalculation of three-dimensional (x,y, ω) reflection profiles from a few physical crystal and instrument parameters. Net intensities are obtained by least-squares fitting the observed profile with the calculated standard using singular value decomposition. This paper shows that profiles can be predicted satisfactorily and that accurate intensities are obtained. The detailed profile analysis has the additional advantage that specific physical properties of the crystal are revealed. TheEVAL15method is particularly useful in circumstances where other programs fail, such as regions of reciprocal space with weak scattering, crystals with anisotropic shape or anisotropic mosaicity,Kα1/Kα2peak splitting, interference from close neighbours, twin lattices, or satellite reflections of modulated structures, all of which may frustrate the customary profile learning and fitting procedures.EVAL15allows the deconvolution of overlapping reflections. |
Plný text