Curtin University Homepage
  • Library
  • Help
    • Admin

    espace - Curtin’s institutional repository

    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item

    A capillary specimen aberration for describing X-ray powder diffraction line profiles for convergent, divergent and parallel beam geometries

    257287.pdf (1.759Mb)
    Access Status
    Open access
    Authors
    Coelho, A.
    Rowles, Matthew
    Date
    2017
    Type
    Journal Article
    
    Metadata
    Show full item record
    Citation
    Coelho, A. and Rowles, M. 2017. A capillary specimen aberration for describing X-ray powder diffraction line profiles for convergent, divergent and parallel beam geometries. Journal of Applied Crystallography. 50: pp. 1331-1340.
    Source Title
    Journal of Applied Crystallography
    DOI
    10.1107/S160057671701130X
    ISSN
    0021-8898
    School
    Department of Physics and Astronomy
    Remarks

    Copyright © International Union of Crystallography

    URI
    http://hdl.handle.net/20.500.11937/58859
    Collection
    • Curtin Research Publications
    Abstract

    X-ray powder diffraction patterns of cylindrical capillary specimens have substantially different peak positions, shapes and intensities relative to patterns from flat specimens. These aberrations vary in a complex manner with diffraction angle and instrument geometry. This paper describes a fast numerical procedure that accurately describes the capillary aberration in the equatorial plane for convergent focusing, divergent and parallel beam instrument geometries. Axial divergence effects are ignored and only a cross section of the capillary, a disc, is considered; it is assumed that axial divergence effects can be described using an additional correction that is independent of the disc correction. Significantly, the present implementation uses the TOPAS-Academic aberration approximation technique of averaging nearby aberrations in 2? space to approximate in-between aberrations, which results in no more than ~30 disc aberrations calculated over the entire 2? range, even when the diffraction pattern comprises thousands of peaks. Finally, the disc aberration is convoluted with the emission profile and other instrument and specimen aberrations in a Rietveld refinement sense, allowing for refinement on the specimen's absorption coefficient and capillary diameter, as well as the instrument focal length. Large differences between refined and expected values give insight into instrument alignment.

    Related items

    Showing items related by title, author, creator and subject.

    • Diffraction-based modelling of microstructural size and strain effects in sintered ceramics
      Pratapa, Suminar (2003)
      Crystallite (or grain) size and strain within a polycrystalline material may have a profound influence on its physical properties, eg. the fracture toughness, wear and thermal shock resistance. A diffraction pattern for ...
    • Size exclusion chromatography as a tool for natural organic matter characterisation in drinking water treatment
      Allpike, Bradley (2008)
      Natural organic matter (NOM), ubiquitous in natural water sources, is generated by biogeochemical processes in both the water body and in the surrounding watershed, as well as from the contribution of organic compounds ...
    • Experimental studies on the interactions between dolomite and SiO2-rich fluids: implications for the formation of carbonate reservoirs
      Wang, Xiaolin; Wan, Ye; Hu, Wenxuan; You, Donghua; Cao, Jian; Zhu, Dongya; Li, Zhen (2017)
      Objectives: Investigating the water-rock interaction mechanism and kinetics between dolomite and silica rich hydrothermal fluids; Discussing the effect of silica rich hydrothermal fluids on the formation of deep carbonate ...
    Advanced search

    Browse

    Communities & CollectionsIssue DateAuthorTitleSubjectDocument TypeThis CollectionIssue DateAuthorTitleSubjectDocument Type

    My Account

    Admin

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Follow Curtin

    • 
    • 
    • 
    • 
    • 

    CRICOS Provider Code: 00301JABN: 99 143 842 569TEQSA: PRV12158

    Copyright | Disclaimer | Privacy statement | Accessibility

    Curtin would like to pay respect to the Aboriginal and Torres Strait Islander members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Whadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.