Phases of Fourier coefficients directly from crystal diffraction data

@article{Harker1948PhasesOF,
  title={Phases of Fourier coefficients directly from crystal diffraction data},
  author={David Harker and John S. Kasper},
  journal={Acta Crystallographica},
  year={1948},
  volume={1},
  pages={70-75}
}
It is shown that the application of Schwarz's and Cauchy's Inequalities to the formulas for calculating Fa** from, respectively, the density of scattering matter and the atomic positions in a crystal leads to relations between the magnitudes of some Fa~,'s and the signs or phases of others. These relations are in the form of inequalities, which vary with the symmetry of the crystal under consideration. A table of the simplest inequalities applicable to crystals possessing each of the simple… Expand

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