SOBRE A LINHA DE LUZ
The XDS beamline is an experimental station dedicated to X-ray Diffraction and Spectroscopy in the hard x-rays (5 to 30 keV) energy range. It focuses on determination of atomic, electronic and magnetic structure of materials with applications to condensed matter physics, chemistry, geosciences, among others. Several sample environments are available at XDS: high pressure cells to subject samples up to 80 GPa, magnetic field of 6 T magnet for diffraction experiments, cryostat for temperatures as low as 1.8 K, furnaces for temperatures up to 1200 K.
The X-ray Diffraction and Spectroscopy (XDS) beamline uses the radiation emitted by the Superconducting Wiggler source and is employed for multipurpose experiments. Some of the diffraction experiments demand control of the horizontal divergence, only achievable with sagittal focusing in a double crystal monochromator. On the other hand, the use of flat crystals and focusing with a toroidal mirror was considered to be the best choice for XAS measurements. These apparently contradictory requirements from the diffraction and absorption community led us to introduce a flexible configuration for this beamline. According to this concept, the beamline operates with a collimating mirror with bender (with Si, Rh and Pt stripes), a double crystal monochromator (DCM) with two interchangeable sets of crystals [plane Si(111), sagittal Si(111) and plane Si(311)], and a focusing mirror with three stripes (toroidal Rh, plane Rh and toroidal Pt) and a bending mechanism to allow for focus adjustments.