Figure 2
GIWAXS images demonstrating the background signal generated by the scattering of the X-ray windows, the atmosphere inside the in situ cell, and the air in between the cell and the detector. The measured intensities are solid-angle- and polarization-corrected. (a) Background without any sample in the beam. (b) Pure glass substrate measured under grazing-incidence conditions (αi = 0.065°). Both measurements were performed at the P08 beamline (PETRA III, DESY) with an X-ray energy of 25 keV, a sample-to-detector distance of 1386.98 mm and an exposure time of 1 s. The shadowing in (a) below qz ≃ −0.2 Å−1 is caused by the size of the outgoing window. This region of the detector is typically not used during GIWAXS, GISAXS and XRR measurements since it is below the projection of the sample horizon on the detector. |