Using a two-dimensional detector for X-ray powder diffractometry

Abstract

Special software has been developed to calculate the intensity-scattering-angle dependence. Powder diffraction patterns are obtained in a diffractometer with a two-dimensional area detector. The detector used is a planar proportional chamber with fast delay lines. The optimum sample geometry for both the transmission and reflection method is considered. The application of the method for powders and for the investigation of phase transitions in liquid crystals is illustrated.

Characterization of Na precipitates in electron irradiated NaCl crystals by wide angle X-ray scattering (WAXS)

“…To determine the line broadening and Na volume percentage in a more straightforward way than in single crystal experiments we have used the KARD6 diffractometer with a 256 £ 256 2D-detector [11]. Cu K aradiation and a graphite monochromator were used.…”

“…a powder pattern of sufficient quality was obtained by averaging the intensity over the whole detector plane. Then we calculated the FWHM for the strongest Na 110 line by profile fitting and compared it with the well-known FWHM of the IRF, which in this case is very close to Gaussian [11]. The powder patterns for two samples are presented in Fig.…”

“…Several reloads were used to improve the averaging over the individual grains. The procedure described in [11] was applied to calculate the intensity vs. the scattering angle function Ið2uÞ; i.e. a powder pattern of sufficient quality was obtained by averaging the intensity over the whole detector plane.…”

A Comparative Study of X ray Diffraction Pattern Obtaining Methods for Portable Diffractometer

“…Eq. ) where: Iij is the integrated profile intensity for the sector i, on ring j; 2θ obs is the calculated 2θ angle based on the ring coordinate and the current model value of the beam centre and tile; 2θ is the current model value of the 2θ angle of the ring j, see [6] for details. variables using only function values, without any derivative information.…”

“…But this method was found to be valid when the half width of the diffraction peak was larger than five pixels. A histogram method was alternatively developed [6]. Intensity at each pixel was plotted as a function of the distance from the direct beam position.…”