| dc.description.abstract-en | Diffractions of (02, 11) band are very sensitive to the structural defects in kaolinite structure. Therefore, the empirical relation based on weighting peak intensity ratio of 0 2 0, 1 (1) over bar 0, and 1 1 (1) over bar (1 (1) over bar (1) over bar) reflections was used to estimate the degree of disorder in kaolinite samples collected from different Czech Republic kaolin deposits. X-ray diffraction (XRD) profiles taken from < 5 mum fraction of kaolinite samples were used for determination of peak intensities I(1 (1) over bar 0), I(1 1 (1) over bar ),I(1 (1) over bar (1) over bar), I(0 2 0) and full width at half maximum (FWHM) values using profile fitting and decomposition procedure. The weighting intensity ratio index (WIRI)
WIRI = 1 - esp{-[w(1)I(1 (1) over bar 0) + w(2)I(1 1 (1) over bar) + w(3)I(1 (1) over bar (1) over bar)]/[w(4)I(0 2 0)]}
was calculated. The w(1), w(2), w(3), and w(4) weight values are the reciprocal values of FWHM for 1 (1) over bar 0, 1 1 (1) over bar, 1 (1) over bar (1) over bar, and 0 2 0 reflections, respectively. According the WIRI values (theoretically ranging from 0 to 1), three groups of kaolinite samples can be recognized: (I) one sample with high degree of structural order (0.70 < WIRI < 1.00), (II) two samples with medium degree of structural order (0.40 < WIRI less than or equal to 0.70), and (III) five samples with low degree of structural order (0.00 < WIRI less than or equal to 0.40). The WIRI values obtained were compared with Hinckley (HI) and Aparicio-Galan-Ferrell (AGFI) indices and very good relations were found between them. | |