BM25A

Synopsis

Branch A is devoted to materials science in the energy range 5-45 keV. The experimental stations enable the performance of X-ray absorption spectroscopy and high-resolution powder diffraction measurements.
Status:  open

Disciplines

  • Physics
  • Chemistry
  • Materials and Engineering
  • Environmental Sciences
  • Cultural Heritage
  • Life Sciences

Applications

  • Materials science

Techniques

  • Powder diffraction
  • XAS - X-ray absorption spectroscopy

Energy range

  • 5.0 - 45.0  keV

Beam size

  • Minimum (H x V) : 0.05 x 0.05  mm²
  • Maximum (H x V) : 40.0 x 10.0  mm²

Sample environments

  • HRPD - capillaries
  • HRPD - in-situ thermal treatment (cooling to 80K, heating to 1000K)
  • XAS - in-situ thermal treatment (4-500K, 300-1300K)
  • XAS - pressure variation (ultra high vacuum to 3 bar)
  • XAS - gas reactor
  • XAS - baby chamber

Detectors

  • 13-element Si(Li) detector from e2v Scientific Instruments

Technical details

1. High-resolution powder diffraction (HRPD) measurements can be performed within a photon energy range between 5 and 45 keV. Hence, K and L-edge resonance experiments can be performed together with non-resonance experiments. An HRPD set-up is installed at the focal plane A2 (~45 m from the source). A heavy-duty theta-two-theta diffractometer with a distance from the center to the detector of at least 50 cm has been installed. The angular resolution for the detector movement is 0.0001 degrees. The main axis for the theta and two-theta circles is horizontal, such that diffraction measurements are realized in the vertical plane. For HRPD samples can be accommodated in capillaries of different diameter according to the available amount of sample or by the concentration of the chemical species present in the sample and the photon energy used. The in-situ thermal treatment systems do not interfere with the detector movement. The HRPD station will be upgraded with the acquisition of a new Theta-TwoTheta diffractometer with a detector stage custom-designed for SpLine. This stage incorporates 10 single point-detectors operated in parallel, and each point detector is equipped with a Ge single crystal analyzer. The diffractometer, which is manufactured by HUBER GmbH, can be used in reflection and transmission (thin films and capillary) configuration and will be delivered and commissioned by the end of 2010. 2. X-Ray absorption spectroscopy measurements can be performed within a photon energy range between 5 and 45 keV. Hence, K and/or L edge for the most relevant chemical species can be scanned. The sample environment has enough free space to install baby chambers, reactors, cryostats, ovens, etc.