International Tables for Crystallography (2006). Vol. F, ch. 13.4, pp. 279-292   | 1 | 2 |
doi: 10.1107/97809553602060000684

Chapter 13.4. Noncrystallographic symmetry averaging of electron density for molecular-replacement phase refinement and extension

Contents

  • 13.4. Noncrystallographic symmetry averaging of electron density for molecular-replacement phase refinement and extension  (pp. 279-292) | html | pdf | chapter contents |
    • 13.4.1. Introduction  (p. 279) | html | pdf |
    • 13.4.2. Noncrystallographic symmetry (NCS)  (pp. 279-280) | html | pdf |
    • 13.4.3. Phase determination using NCS  (pp. 280-281) | html | pdf |
    • 13.4.4. The p - and h -cells  (pp. 281-282) | html | pdf |
    • 13.4.5. Combining crystallographic and noncrystallographic symmetry  (pp. 282-283) | html | pdf |
      • 13.4.5.1. General considerations  (p. 282) | html | pdf |
      • 13.4.5.2. Averaging with the p -cell  (pp. 282-283) | html | pdf |
      • 13.4.5.3. Averaging the p -cell and placing the results into the h -cell  (p. 283) | html | pdf |
    • 13.4.6. Determining the molecular envelope  (pp. 283-284) | html | pdf |
    • 13.4.7. Finding the averaged density  (pp. 284-285) | html | pdf |
    • 13.4.8. Interpolation  (p. 285) | html | pdf |
    • 13.4.9. Combining different crystal forms  (p. 285) | html | pdf |
    • 13.4.10. Phase extension and refinement of the NCS parameters  (pp. 285-286) | html | pdf |
    • 13.4.11. Convergence  (p. 286) | html | pdf |
    • 13.4.12. Ab initio phasing starts  (pp. 286-287) | html | pdf |
    • 13.4.13. Recent salient examples in low-symmetry cases: multidomain averaging and systematic applications of multiple-crystal-form averaging   (pp. 287-288) | html | pdf |
    • 13.4.14. Programs  (p. 288) | html | pdf |
    • References | html | pdf |
    • Figures
      • Fig. 13.4.2.1. The two-dimensional periodic design shows crystallographic twofold axes perpendicular to the page and local noncrystallographic rotation axes in the plane of the paper (design by Audrey Rossmann)  (p. 279) | html | pdf |
      • Fig. 13.4.2.2. ( a ) NCS in a triclinic cell  (p. 280) | html | pdf |
      • Fig. 13.4.2.3. The position of the twofold rotation axis which relates the two piglets is completely arbitrary  (p. 280) | html | pdf |
      • Fig. 13.4.4.1. Stereographic projections showing alternative definitions of the `standard orientation' of an icosahedron in the h -cell  (p. 281) | html | pdf |
      • Fig. 13.4.6.1. The volume of the molecular mask expressed as a percentage of the volume of the p -cell asymmetric unit, as determined by the density cutoff in the h -cell  (p. 284) | html | pdf |
      • Fig. 13.4.8.1. Interpolation box for finding the approximate electron density at G x , Δ y , Δ z ), given the eight densities at the corners of the box  (p. 285) | html | pdf |
      • Fig. 13.4.11.1. Plot of a correlation coefficient as the phases were extended from 8 to 3 Å resolution in the structure determination of Mengo virus  (p. 286) | html | pdf |
      • Fig. 13.4.12.1. Structure amplitudes of the type II crystals of southern bean mosaic virus, averaged within shells of reciprocal space, shown in relation to the Fourier transform of a 284 Å diameter sphere  (p. 287) | html | pdf |
    • Tables
      • Table 13.4.7.1. Mean root-mean-square scatter between noncrystallographically related points  (p. 284) | html | pdf |