W Tungsten

The formation of O2- principal anions by conjunction of O2 molecules with a Na pre-covered MgO surface is forced by a combined EPR and quantum chemical method. Na atoms deposited on polycrystalline MgO samples are brought into get in touch with with O2. The typical EPR signal of out-of-the-way Na atoms disappears when the feedback with O2 takes purpose and new paramagnetic species are observed, which are attributed to peculiar surface-stabilised O2- radicals. Hyperfine sublevel correlation (HYSCORE) spectroscopy allows the superhyperfine interaction tensor of O2-Na+ species to be determined, demonstrating the lineal coordination of the O2- adsorbate to boundary Na+ cations. DFT calculations authorize the structural details of the formed species to be decided. Matrix-isolated alkali superoxides are cast-off as a insigne singular of insignia to approve point of agreement of the formed species, revealing snobbish and unexpected contributions of the MgO matrix in determining the electronic organization of the surface-stabilised Na+[bond]O2- complexes <<>>