The following articles are a selection of those recently accepted for publication in Acta Crystallographica Section A: Foundations of Crystallography.
See also Forthcoming articles in all IUCr journals.
Synopsis: A new diffraction data analysis method for SFX is proposed. This method is found to obtain satisfactory results.
Synopsis: An efficient procedure and computer program have been developed to perform an accurate parameterization for the scattering factors with the correct inclusion of all physical constraints.
Synopsis: Diffuse Scattering from PZN (PbZnNbO3) has been analysed by combining the average structure revealed by Bragg diffraction with the requirements of the bond-valence sum. This goes beyond previous models, which are more prescriptive and artificial in nature, although not all key aspects of the short-range order can be shown to arise `naturally' out of the modelled interactions.
Synopsis: The revealed one-to-one correspondence between a set of cosets of the Mathieu group M11, block sets of the Steiner system S (4, 5, 11) and 11-vertex equiedged triangulated clusters determines symmetry allowable transformations between different 11-vertex triangulated clusters as automorphisms of the Steiner system S (4, 5, 11). The said transformations can describe local reconstructions corresponding to polymorphic transformations in metals.
Synopsis: Accurate atomic displacement parameters obtained from time-of-flight single-crystal diffraction neutron data, collected at the newly commissioned SNS beamline TOPAZ, are presented for two organic crystals and compared to those obtained from four alternative methods: experimental charge density modelling, high order independent atom models, estimates from combined TLS analysis and literature values as implemented in SHADE, and Hirshfeld atom refinement based on X-ray diffraction data.
Synopsis: An algorithm for calculating the 2 diffraction profiles is developed based on the dynamical theory of X-ray diffraction for multi-beam cases. The connection between the 2 scanned profiles and the excitation of mode is revealed.
Synopsis: All homogeneous sphere packings were derived that refer to the trivariant orthorhombic lattice complexes of the space groups belonging to crystal class 222.
Synopsis: The application of the Ratio method in processing/analysis prior to structure refinement requires an appropriate ratio model for modeling the light response. Such a model is discussed, taking into account both geometric and thermal light-induced changes.
Synopsis: Methods for the detection and visualization of systematic errors in measurement data are developed on the basis of conditional probabilities and applied to artificial and experimental data from the literature.
Synopsis: Different X-ray refinement methods for modelling hydrogen bonds in the compound L-phenylalaninium hydrogen maleate are compared. It is found that Hirshfeld atom refinement (HAR) produces bond lengths involving hydrogen atoms in agreement with benchmarking results from neutron diffraction, and it is the only X-ray method to obtain a symmetric hydrogen site in the intramolecular hydrogen bond of this compound. Residual-density distributions in HAR are better than in the multipole-based models.
Synopsis: Revised Seitz notation is provided for the symmetry operations blocks of the International Tables for Crystallography Vol. E, Subperiodic Groups.
Synopsis: An approach has been developed for the first time to determine the displacive and substitutional modulation functions of an incommensurate modulated structure from a limited-size high-resolution transmission electron microscope image and electron diffraction data.
Synopsis: The radial projection method for locally finite planar point sets is explored and numerical examples for different types of order are provided.
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