A novel ultra-high vacuum instrument for X-ray reflectometry and spectrometry-related techniques for nanoanalytics by means of synchrotron radiation has been constructed and commissioned. This versatile instrument was developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute, and includes a 9-axis manipulator that allows for an independent alignment of the samples with respect to all degrees of freedom. In addition, a rotational and translational movement of several photodiodes as well as a translational movement of an aperture system in and out of the beam is provided. Thus, the new instrument enables various analytical techniques based on energy dispersive X-ray detectors such as reference-free X-ray fluorescence analysis (XRF), total-reflection XRF, grazing-incidence XRF in addition to optional X-ray reflectometry measurements or polarization-dependent X-ray absorption fine structure analyses. With this instrument samples having a size of up to 100 mm × 100 mm can be analyzed with respect to their mass deposition, elemental or spatial composition, or the species in order to probe surface contamination, layer composition and thickness, the depth profile of matrix elements or implants, the species of nanolayers, nanoparticles or buried interfaces as well as the molecular orientation of bonds. Selected applications of this advanced ultra-high vacuum instrument demonstrate both its flexibility and capability.

We present valence-to-core x-ray emission spectroscopy of Ti, TiO and TiO2 by means of a double crystal von Hamos spectrometer based on full-cylinder highly-annealed pyrolytic graphite mosaic crystals. We demonstrate that, using a double crystal configuration, an energy resolution of E/ΔE ≈ 2700 can be achieved in a compact setup using cylindrically curved optics with a radius of curvature of 50 mm. The stated energy resolution proved to be high enough to identify and determine chemical shifts of the Kβ2,5 and Kβ” emission lines of both oxides. The experimental results are supported by calculations with the ab initio package OCEAN and compared to literature values.

Highly annealed pyrolytic graphite (HAPG) is an advanced type of pyrolytic graphite that, as a mosaic crystal, combines high integral reflectivity with a very low mosaicity of typically less than 0.1°. When used as dispersive X‐ray optics, a high resolving power has been observed, rendering HAPG very suitable for applications in high‐resolution X‐ray spectroscopy, which conventionally relies on ideal crystals. For the design and modelling of HAPG crystals in applications requiring high spectral resolution, the diffraction properties must be known very accurately. To close this gap, a comprehensive characterization of HAPG crystals was performed that allows for modelling of the diffraction properties in different diffraction orders over a broad spectral range. The crystal properties under investigation are the mosaic spread, the peak reflectivity and the intrinsic reflection width. The investigations were carried out for different thickness crystal films, which were mounted adhesively on a substrate. It is shown that the diffraction properties are strongly correlated to the grade of adhesion, which depends crucially on the substrate material and its surface properties. The investigations were performed using monochromated tunable synchrotron radiation of high spectral purity with a high‐precision experimental setup and calibrated detection devices at the electron storage ring BESSY II.

In this work the complete L-emission spectrum of gadolinium with respect to line energies, natural line widths, and relative transition probabilities was investigated using monochromatized synchrotron radiation. The measurements were realized in the PTB laboratory at BESSY II by means of an in-house built von Hamos spectrometer based on up to two full-cylinder HAPG mosaic crystal. The von Hamos spectrometer is calibrated by means of elastically scattered photons from the employed synchrotron radiation beamline leading to a well-defined energy scale and an experimentally determined spectrometer response. A selective excitation of the gadolinium L subshells was carried out to ensure a robust deconvolution of neighboring emission lines of different L subshells. The experimental results are discussed in the context of existing data from common databases and published values since significant deviations, especially for the Lγ 2 and Lγ 3 emission lines, are observed. We further substantiate and discuss two satellite lines at the low-energy side of the Lβ 2,15 and Lγ 1 emission lines arising from the N 4,5 subshell. 12/1515/15

A novel double full-cylinder crystal x-ray spectrometer for x-ray emission spectroscopy (XES) has been realized based on a modified von Hamos geometry. The spectrometer is characterized by its compact dimensions, its versatility with respect to the number of crystals used in series in the detection path, and the option to perform calibrated XES measurements. The full-cylinder crystals used are based on highly annealed pyrolytic graphite with a thickness of 40 μm, which was bent to a radius of curvature of 50 mm. The flexible design of the spectrometer allows for an easy change—within the same setup—between measurements with one crystal for maximized efficiency or two crystals for increased spectral resolving power. The spectrometer realized can be used at different end-stations of synchrotron radiation beamlines or can be laboratory-based. The main application focus of the spectrometer is the determination of x-ray fundamental atomic parameters in the photon energy range from 2.4 to 18 keV. The evaluation of chemical speciation is also an area of application, as demonstrated in the example of battery electrodes using resonant inelastic x-ray scattering.