forthcoming articles

Treatment of the effects of a single-crystal incident-beam monochromator in a powder diffraction experiment must be carried out using dynamical diffraction to obtain the correct intensities for reflections, due to the modification of the beam polarization by the monochromator. Theory and data are presented to verify the effect.

The resolution function of a bent-crystal spectrometer for pulses of an X-ray free-electron laser is evaluated. Under appropriate conditions, the energy resolution reaches the ratio of the lattice spacing to the crystal thickness.

A new multi-lattice indexing method based on the principle of whole-pattern matching given cell dimensions and space-group symmetry is presented for macromolecular crystallography. The proposed method features a local correction for prior information accompanied by iterative refinement of experimental parameters, both of which are numerically and experimentally demonstrated to be critical for accurately identifying multiple crystal lattices.

By appropriate reformulation of relativistic spacetime geometry, a direct mapping to Euclidean space crystals is shown. Using this mapping, hidden symmetries in relativistic spacetime crystals are uncovered.

The ubiquity of the icosahedral symmetry among various spherical molecules, fullerenes and viruses motivates the current study. The structures of dual polytopes with the H₃ symmetry obtained for seven types of dominant points are described in detail. The existence of the corresponding nanotubes is explained using a symmetry-breaking mechanism. The structure of the fullerene C₂₀ is expanded into the nanotubes C_20+6N and C_20+10N, using the reduction of the icosahedral symmetry to the subgroups A₂ and H₂, respectively.