Uranium-oxide-based catalysts for the destruction of volatile chloro-organic compounds

Role of resonant inelastic X-ray scattering in high-resolution core-level spectroscopy of actinide materials

“…The paths of the incident and emitted X-rays through the air during the experiment at the U M edges were minimized in order to avoid losses in intensity due absorption in the air. The polycrystalline materials U 3 12 and single crystal UO 2 were covered by 50 µm Kapton film and did not show any radiation damage.…”

“…This provides motivation for scientists to study the fundamental and applied properties of actinide systems in connection with their synthesis [2][3] , oxidation 4 , corrosion 5 , reprocessing 6 and migration 7 , stability at extreme conditions [8][9] , environmental impact 10 and disposal of nuclear waste 11 . Obviously, the development of new and beneficial use of depleted uranium may extend the application beyond the nuclear industry [6][7]12 . Characterization of U in different materials is essential for the future management of such substances.…”

The electronic spectrum of CUONg4 (Ng = Ne, Ar, Kr, Xe): New insights in the interaction of the CUO molecule with noble gas matrices

“…In Figure 3(a) we plot the energy difference of all relevant virtual orbitals relative to the HOMO to get a first indication of the effect of the environment on excitation energies. The diffuse non-bonding σ -orbital, which is the LUMO in bare CUO and CUONe 4 , is pushed up by the repulsive interaction with the closed-shell ligands and rises in the argon system above the φ-orbitals, and in krypton and xenon also above the lower δ-orbital 27a 1 . This indicates that this orbital is indeed of less interest in explaining the electronic structure of the molecule in the matrix.…”

“…For every molecule we determined the 30 lowest-lying (singlet and triplet) states, which was sufficient to characterize the 22 transitions corresponding to excitations from the 25a 1 ( f σ {U} + p σ {C}) and 12b 1 /b 2 ( f π {U}) orbitals to the 26a 1 In the FDE setup the total electronic density of the CUO complexes (CUONg 4 , Ng=Ne, Ar, Kr, Xe) was partitioned into the density of CUO and a Ng 4 environment and subsequently updated in nine freeze-and-thaw cycles 75 to allow for polarization of both the environment and the active system. We utilized the monomolecular basis set expansion, in which only basis functions belonging to the currently active system are used.…”

“…1,2 This is due to uranium's wide range of oxidation states (+6, +5, +4 and +3) and coordination geometries. [3][4][5][6] These features arise from the availability of the spatially rather different 5f-, 6d-, 7s-, and 7p-orbitals that are energetically close and do participate in the chemical bonding.…”