Phase Determination in the X-Ray Diffraction Patterns of Complex Crystals and its Application to Protein Structure

@article{Bernal1952PhaseDI,
  title={Phase Determination in the X-Ray Diffraction Patterns of Complex Crystals and its Application to Protein Structure},
  author={John Desmond Bernal},
  journal={Nature},
  year={1952},
  volume={169},
  pages={1007-1008}
}
THE phases, or signs in cases of central symmetry, of X-ray reflexions from organic crystals can only be determined unambiguously and without prior assumptions by the use of methods employing heavy atoms or isomorphous replacements. In cases where these methods cannot be used, they have been determined hitherto largely either by means of conjectural molecular models with subsequent refinement, or by the use of various inequalities such as those of Harker and Kasper1 and later elaborations, all… Expand
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References

Phases of Fourier coefficients directly from crystal diffraction data
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 crystalExpand