Novel microfocus X-ray sources for high-pressure crystallography

Abstract

Beam Characteristics of the IμS The Ag-IμS delivers a focused and monochromatic X-ray beam with a FWHM of 0.09 mm in the image focus. In contrast to the typical top-hat shaped beam profile that is produced by sources coupled to a flat graphite monochromator, the beam profile from the IμS has a symmetrical Gaussian-shaped intensity distribution. As a consequence, the flux density increases with decreasing sample size (Fig. 1), thus leading to strong diffracted intensities especially for small samples. Furthermore, the convergent beam from the IμS reduces the background of the data by minimizing the scattering from peripherals, such as conventional crystal mounts or gaskets. The integrated intensity of the original Ag-IμS, which is available since 2009, is at least about three times higher than the intensity of a 1.5 kW Ag sealed tube system. The new Ag-IμSHigh Brilliance has an improved X-ray optical design that results in a further intensity gain of 50% when compared to the original Ag-IμS.