We calculate the angular dependence of the x-ray linear and circular dichroism at the L2,3 edges of α-Fe(II) Phthalocyanine (FePc) thin films using a ligand field model with full configuration interaction. We find the best agreement with the experimental spectra for a mixed ground state of 3 Eg(a ) with the two configurations coupled by the spin-orbit interaction. The 3 Eg(b) and 3 B2g states have an easy axis and plane anisotropies, respectively. Our model accounts for an easy-plane magnetic anisotropy and the measured magnitudes of the in-plane orbital and spin moments. The proximity in energy of the two configurations allows a switching of the magnetic anisotropy from easy plane to easy axis with a small change in the crystal field, as recently observed for FePc adsorbed on an oxidized Cu surface. We also discuss the possibility of a quintet ground state ( 5 A1g is 250 meV above the ground state) with planar anisotropy by manipulation of the Fe-C bond length by depositing the complex on a substrate that is subjected to a mechanical strain.

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Olive tree pruning was delignified by organosolv processes (acetosolv, formosolv, and acetosolv/formosolv) to extract different lignins. The obtained lignins (acetosolv lignin (AL), formosolv lignin (FL), and acetosolv/formosolv lignin (AFL)) were depolymerized using three different solvents (methanol, ethanol, and acetone) under supercritical conditions in a batch reactor to produce high value-added compounds. The recovered products (oil, char, and residual lignin) were analyzed in order to determine their composition and to know the influence of employed solvent and lignin. Lignin was successfully depolymerized in all cases, and the molecular weight of residual lignin was significantly reduced compared to raw lignin. The obtained oil had numerous phenolic monomers, with syringol and guaiacol being the main products in all studied cases. Depolymerization of AFL led to maximum yield of oil (38.04%), and acetone was the best solvent in terms of phenolic monomers production.

We have investigated the antiferromagnetic insulating phase of the Mott-Hubbard insulator V 2 O 3 by resonant x-ray Bragg diffraction at the vanadium K-edge. Combining the information obtained from azimuthal angle scans, linear incoming polarization scans and by fitting collected data to the scattering amplitude derived from the established chemical I2/a and magnetic space groups we provide evidence of the ordering motif of anapolar moments (which results from parity violation coupling to an electromagnetic field). Experimental data (azimuthal dependence and polarization analysis) collected at space-group forbidden Bragg reflections are successfully accounted within our model in terms of vanadium magnetoelectric multipoles. We demonstrate that resonant x-ray diffraction intensities in all space-group forbidden Bragg reflections of the kind (hkl) m with odd h are produced by an E1-E2 event. The determined tensorial parameters offer a test for ab-initio calculations in this material, that can lead to a deeper and more quantitative understanding of the physical properties of V 2 O 3 .

Xclaim (x-ray core level atomic multiplets) is a graphical interface for the calculation of corehole spectroscopy and ground state properties within a charge-transfer multiplet model taking into account a many-body Hamiltonian with Coulomb, spin-orbit, crystal-field, and hybridization interactions. Using Coulomb and spin-orbit parameters calculated in the Hartree-Fock limit and ligand field parameters (crystal-field, hybridization and charge-transfer energy) the program calculates x-ray absorption spectroscopy (XAS), x-ray photoemission spectroscopy (XPS), photoemission spectroscopy (PES) and inverse photoemission (IPES). The program runs on Linux, Windows and MacOS platforms.

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