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Disordered lithium-rich transition metal oxyfluorides with a general formula Li$_{1+x}$MO$_{2}$F$_{x}$ (M being a transition metal) are gaining more attention due to their high specific capacity which can be delivered from the facecentered cubic (fcc) structure. The most common synthesis procedure involves use of mechanosynthesis. In this work, ceramic synthesis of lithium rich iron oxyfluoride and lithium rich titanium oxyfluoride are reported. Two ceramic synthesis routes are developed each leading to the different level of doping with Li and F and different levels of cationic disorder in the structure. Three different Li$_{1+x}$MO$_{2}$F$_{x}$ samples (x ¼ 0.25, 0.3 and 1) are compared with a sample prepared by mechanochemical synthesis and non-doped LiFeO2 with fcc structure. The obtained lithium rich iron oxyfluoride are characterized by use of M€ossbauer spectroscopy, X-ray absorption spectroscopy, NMR and TEM. Successful incorporation of Li and F have been confirmed and specific capacity that can be obtained from the samples is in the correlation with the level of disorder introduced with doping, nevertheless oxidation state of iron in all samples is very similar. Conclusions obtained from lithium rich iron oxyfluoride are validated by lithium rich titanium oxyfluoride.

The European Synchrotron and free-electron laser User Organisation (ESUO) represents about 22.000 users from 30 European member states and associated countries. Each country is represented within ESUO by one up to four national delegate(s), depending on the size of the user community in the respective country. The ESUO aims and activities are shown in this poster.

The European Synchrotron and free-electron laser User Organisation (ESUO) established in 2010 represents about 22.000 users. It is composed of 30 member countries. Our vision is to support a thriving (European) synchrotron and FEL user community with equal opportunities of access and participation for all scientists, based solely on the scientific merit of their ideas.

The European Synchrotron and free-electron laser User Organisation (ESUO) established in 2010 represents about 22.000 users. It is composed of 30 member countries. Our vision is to support a thriving (European) synchrotron and FEL user community with equal opportunities of access and participation for all scientists, based solely on the scientific merit of their ideas.

The European Synchrotron and free-electron laser User Organisation (ESUO) established in 2010 today represents about 30.000 users. We aim at representing the users from all European countries. Each country is represented within ESUO by one up to four national delegate(s), depending on the size of the user community in the respective country. The ESUO aims and activities are shown in this poster.

Extra-large pore aluminophosphate molecular sieve TiVPI-5 was synthesised hydrothermally in the presence of di-n-butylamine and transformed by the calcination process at 500 °C to a large pore TAPO-8. Incorporation of titanium(IV) into VPI-5 framework was studied by elemental and thermogravimetric analyses, combined with X-ray Absorption Near Edge Structure (XANES) spectroscopy and UV-VIS absorption spectroscopy. We found that titanium(IV) incorporated in TiVPI-5 isomorphously substitutes framework aluminium on octahedral sites and that it is not present in the structure in the form of TiO2 anatase. In situ IR measurements of pyridine adsorption/desorption were used to check the presence of catalytically active centres in the product resulting from titanium incorporation into the VPI-5 framework. Weak Lewis and Brønsted acid sites were found in small amounts in the calcined product TAPO-8.

Physical review / B 59(4), 3078 - 3081 (1999). doi:10.1103/PhysRevA.59.3078, By removing the structural x-ray-absorption fine-structure signal from K-edge absorption spectra of 4pelements from Ga to Br in chalcogenide glasses and other samples, the pure atomic absorption is recovered. Its main components are shake-up and shake-off channels of the [1s3p] and [1s3d] group. The [1s3p]4p shake-up channel is observed to close off along the series as the 4p shell is progressively filled., Published by Inst.8644, Woodbury, NY

Physical review / B 45(7), 4682 - 4687 (1992). doi:10.1103/PhysRevA.45.4682, The x-ray absorption of transition metals from Cr to Zn is examined in the energy region of K+L double photoabsorption. A variational procedure is developed to extract correlated components from pairs of spectra. Applied to absorption spectra taken at different sample temperatures, the procedure is used to suppress the extended x-ray-absorption fine-structure oscillations that pervade the K+L region in this range of elements. A relative sensitivity of 2×10$^{−3}$ to 3×10$^{−4}$ of the absorption coefficient, depending on the sample quality, is achieved. No significant features attributable to multiple photoexcitation are found in the spectra on that level, so that previous reports of K+L edges for Co, Ni, and Zn are not confirmed., Published by Inst.8644, Woodbury, NY