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Maximum entropy method and charge flipping, a powerful combination to visualize the true nature of structural disorder from in situ X-ray powder diffraction data
Acta Cryst. (2010). B66, 184–195 (doi.org/10.1107/S0108768109052616)
Completely ab initio electron-density distributions have been obtained from X-ray powder diffraction data by the maximum entropy method (MEM) applied to the combination of structure-factor amplitudes from Le Bail fits with phases derived from charge flipping with histogram matching. This approach bears the potential of a fast method of electron-density determination without the need for a structure model, and will be especially useful for highly disordered materials. The figure shows such an ab initio density of the disordered high-temperature phase of Rb2C2O4.
A. Samy, R. E. Dinnebier, S. van Smaalen and M. Jansen