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The FinEstBeaMS beamline is under construction at the 1.5 GeV storage ring of the MAX IV Laboratory at Lund, Sweden. It has been designed to cover an unusually wide energy range from ultraviolet (4.3 eV) to soft X-rays (1000 eV) but experiments will also be possible at the Mg and Al Kα energies. Instead of having two different insertion devices and optical schemes for low and high photon energy regions, we have based our design on a single long-period, elliptically polarizing undulator and a plane grating monochromator. This solution will provide very good conditions for planned experiments in the whole photon energy region. The beamline will have two branches: one will mainly be used to investigate free atoms, molecules and clusters with photoelectron/photoion coincidence spectroscopy as well as solids with photoluminescence spectroscopy whereas the other one will be dedicated to ultra-high vacuum studies of surfaces and interfaces, utilizing X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. This paper focuses on the optical design of the beamline and general design concepts of the gas phase and solid state end stations.

Background: The ratio of volume flow in the common femoral vein and artery denoted as venous-arterial Flowindex (VAFI) is significantly increased in venous insufficiency according the clinical grade of the disease. This study was done to investigate the reliability and reproducibility of VAFI as quantitative pattern. Patients and methods: In 43 patients with varicose veins C4–6 EPAS,D,PPR (PVV), 40 with postthrombotic syndrome C4–6 ESAS,D,PPR,O (PTS) and 48 healthy volunteers volume flow in the common femoral vein (VFV) and artery (VFA) were measured by duplex. Division of VFV by VFA calculated VAFI. VAFI-measurement was repeated 5 times at an interval of ten minutes in 63 subjects (23 PVV, 20 PTS, 20 healthy) and it was performed at three different days in 68 subjects (20 PVV, 20 PTS, 28 healthy). Results: Mean VAFI ± standard deviation was 1.39 ± 0.26 in PVV, 1.42 ± 0.26 in PTS and 0.93 ± 0.13 in healthy veins (p < 0.001). VAFI remained stable and significantly increased (p < 0.001) in PVV and PTS compared to healthy veins during 40 minutes and also within three different days. Conclusion: The venous-arterial flowindex VAFI is a reproducible pattern of the hemodynamic severity in venous insufficiency.

A detailed study of inelastic x-ray scattering from the ground state to the (3)Sigma(g)(3 sigma(-1)(g)3s(g)(1)) state of the O-2 molecule is presented. The observed angular anisotropy shows that the vibrational excitations within this final state are strongly dependent on the polarization of the incident radiation. The analysis demonstrates that this is a manifestation of interference between resonant and direct nonresonant inelastic x-ray scattering. This interference provides a new tool to monitor nuclear dynamics by relative rotation of the polarization vectors of the incident and scattered photons.

X-ray spectroscopy studies of potassium intercalated metal-free phthalocyanine multilayers adsorbed on Al(110) have been undertaken. Photoelectron spectroscopy measurements show the presence of several charge states of the molecules upon K intercalation, due to a charge transfer from the alkali. In addition, the comparison of valence band photoemission spectra with the density functional theory calculations of the density of states of the H2Pc- anion indicates a filling of the formerly lowest unoccupied molecular orbital by charge transfer from the alkali. This is further confirmed by x-ray absorption spectroscopy (XAS) studies, which show a decreased density of unoccupied states. XAS measurements in different experimental geometries reveal that the molecules in the pristine film are standing upright on the surface or are only slightly tilted away from the surface normal but upon K intercalation, the molecular orientation is changed in that the tilt angle of the molecules increases. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4738755]

Symmetrical fluorescence yield profiles and asymmetrical electron yield profiles of the preresonances at the La N-IV,N-V x-ray absorption edge are experimentally observed in LaPO4 nanoparticles. Theoretical studies show that they are caused by interference effects. The spin-orbit interaction and the giant resonance produce symmetry entangled intermediate states that activate coherent scattering and alter the spectral distribution of the oscillator strength. The scattering amplitudes of the electron and fluorescence decays are further modified by the spin-orbit coupling in the final 5p(5)epsilon l and 5p(5)4f(1) states.

In the light of hybrid functional density-functional theory calculations of the core-excited and core-ionized states, this paper discusses original N 1s x-ray photoemission spectroscopy (XPS) and near-edge x-ray absorption fine-structure (NEXAFS) experimental data on the single-domain (vicinal) Si(001)- 2×1 surface saturated by NH3 at 300 K. The theoretical approach enables to discuss the vibrational shape of the N 1s XPS spectrum and quantifies the binding-energy splitting due to intrarow and inter-row hydrogen bondings between amine pairs. The observed N 1s NEXAFS peaks are interpreted through the analysis of the contour maps of the antibonding Kohn-Sham orbitals of the NH2 adsorbate and through the ? Kohn-Sham calculation of the transition energies, laying a theoretical basis for a discussion of the adsorbate spatial orientation. Finally, suggestions are given for future directions of research to get a further knowledge of a system that has potential applications as a template for molecular layer deposition and supramolecular assembly.

Physical review / A 75, 51406 (2007). doi:10.1103/PhysRevA.75.051406, Published by APS, College Park, Md.

Physical review / A 76(1), 1341 (2007). doi:10.1103/PhysRevA.76.013411, Published by APS, College Park, Md.

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