Increasing data completeness in synchrotron tts-microdiffraction experiments for δ-recycling phasing of low-symmetry compounds

Abstract

Successful phasing of synchrotron through-the-substrate microdiffraction data by

d2Dplot: 2D X-ray diffraction data processing and analysis for through-the-substrate microdiffraction

“…This is one of its main features which also complements the tts-XRD methodology for the analysis of transmission diffraction data from thin sections mounted on glass substrates (Rius et al, 2015). tts-XRD consists of a series of measurements at selected sample points by using the rotation method with wide angular overlapping increments (typically between 5 and 15 ) to cope with eventual diffracting volume variations along the section depth during the measurements (Rius, Vallcorba, Crespi & Colombo, 2017). The orientation of the crystal(s) is then found, and the intensities are extracted and scaled by using all the measurements.…”

Novel phasing method using the origin-free modulus sum function expressed in terms of the absolute electron density

“…While charge-flipping works exclusively with pixels (no Fourier peaks are searched during the iteration), both -recycling and intrinsic phasing assume atoms in different ways and hence are appropriate for moderate-quality data or moderately incomplete data sets (see e.g. Rius et al, 2013Rius et al, , 2017. The S M -FFT and the standard VLD algorithms both require the calculation of four Fourier transforms (instead of two) to complete one iteration.…”