Record details

    Characterization of intercalated smectites using XRD profile analysis in the low-angle region
Statement of responsibility
    Daniel Janeba, Pavla Čapková, Zdeněk Weiss, Henk Schenk
    Čapková, Pavla
    Janeba, Daniel
    Schenk, Henk
    Weiss, Zdeněk
Source title - serial
    Clays and clay minerals
    Vol. 46, no. 1
    p. 63-68
    7 obr., 1 tab., 11 bibl.
    Zkr. název ser.: Clays and Clay Miner.
Subject group
    difrakce rentgenová
    krystalová struktura
    minerály jílové
Abstract (in english)
   -ray diffraction (XRD) characterization of natural and intercalated smectites is usually limited to the apparent d-value estimated from the peak maxima in the raw data. This can lead to the misinterpretation of the measured data. In the case of XRD, the interference function is modulated by instrumental factors (Lorentz-polarization factor, diffraction geometry) and physical factors (structure factor, surface roughness effect). These effects lead to diffraction profile distortions, depending on the difraction angle and peak full width at half maximum (FWHM). As result, the diffraction profiles for structures with large line brodening (FWHM 1) exhibit a significant peak shift (Ad-1.5A), especially at low angles (20 10). The present work deals with the detailed analysis of all these effects, their corrections and their consequences for the interpreatation of diffraction patterns (including possible errors in determining lattice parameters or the structure model).
   The investigated materials were montmorillonites (MMT) intercalated with hydroxy-Al polymers. Diffraction profile analysis revealed the corrected d-values and showed that the intercalated sample is not a mixed-layered structure. As a result a structural model of the interlayer is presented
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
Entered date
    21. 3. 2008
Import date
    8. 8. 2012