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We present a novel, highly efficient von Hamos spectrometer for X-ray emission spectroscopy (XES) in the laboratory using highly annealed pyrolitic graphite crystals as the dispersive element. The spectrometer covers an energy range from 2.5 keV to 15 keV giving access to chemical speciation and information about the electronic configuration of 3d transition metals by means of the Kβ multiplet. XES spectra of Ti compounds are presented to demonstrate the speciation capabilities of the instrument. A spectral resolving power of E/ΔE = 2000 at 8 keV was achieved. Typical acquisition times range from 10 min for bulk material to hours for thin samples below 1 μm.

The recently developed 3D micro X-ray fluorescence spectroscopy (3D Micro-XRF) enables three-dimensional resolved, nondestructive investigation of elemental distribution in samples in the micrometer regime. Establishing a reliable quantification procedure is the precondition to render this spectroscopic method into a true analytical tool. One prominent field of application is the investigation of stratified material. A procedure for the quantitative reconstruction of the composition of stratified material by means of 3D Micro-XRF is proposed and validated. With the procedure, it is now possible to determine nondestructively the chemical composition and the thickness of layers. As no adequate stratified reference samples were available for validation, stratified reference material has been developed that is appropriate for 3D Micro-XRF or other depth-sensitive X-ray techniques.

The qualitative and quantitative investigation of historical iron-gall inks using micro-XRF spectrometry is a suitable method for analyzing composition fingerprints of different ink types. The quantitative analysis is based on a model that takes into account the inhomogeneity and the layer structure of archaeometric samples. Starting from these composition fingerprints, it is possible to characterize distinguishable inks of one artist to classify different chronological ink types and, further, to date unknown fragments that have not so far been integrated into the lifework of an artist. The first qualitative and quantitative investigations of the manuscript 'Faust I and II' and of the music composition 'The Magic Flute' demonstrate impressively the identification of J. W. v. Goethe's and W. A. Mozart's artistic work with modern scientific methods. Further investigations on A. v. Arnim's manuscript 'Studien zu Naturwissenschaften' provide evidence that the diversity of various degradation mechanisms of iron-gall inks could be mainly caused by different inorganic compositions.

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We have built a laboratory spectrometer for X-ray emission spectroscopy. The instrument is employed in catalysis research. The key component is a von Hamos full cylinder optic with Highly Annealed Pyrolytic Graphite (HAPG) as a dispersive element. With this very efficient optic, the spectrometer subtends an effective solid angle of detection of around 1 msr, allowing for the analysis of dilute samples. The resolving power of the spectrometer is approximately E/∆E = 4000, with an energy range of ∼2.3 keV-10 keV. The instrument and its characteristics are described herein. Further, a comparison with a prototype spectrometer, based on the same principle, shows the substantial improvement in the spectral resolution and energy range for the present setup. The paper concludes with a discussion of sample handling. A compilation of HAPG fundamentals and related publications are given in a brief Appendix.

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a This paper presents recent achievements in laboratory based instrumentation for X-ray Absorption Fine Structure Spectroscopy (XAFS). The key component of the spectrometer is a HAPG mosaic crystal, which is employed in the von Hamos geometry. Due to the high efficiency of HAPG a low power micro focus X-ray tube can serve as an X-ray source. Besides a description of the spectrometer, the paper covers the treatment of the CCD images in detail. The latter is crucial in order to entirely exploit the potential of the HAPG (Highly Annealed Pyrolitic Graphite) spectrometer. One section is dedicated to applications. As a first kind of application, the concentrations of two different iron species in mixtures are determined. A second kind of typical usage of XAFS is the determination of bond lengths from the EXAFS. This XAFS application is demonstrated with metallic Ni as a reference material.