SURFACE CHARACTERIZATION OF THE CUO MGF2 SYSTEM/

As a result of ESR and IR studies two kinds of Cu(II) complexes have b een evidenced on the surface of CuO/MgF2 preparations: copper-oxide an d copper-fluoride octahedra. The copper-oxygen complex is characterist ic of a low temperature process (423 K), while the other complex of co pper (II) with the fluoride ligands appears at higher temperatures (57 3, 673 K) of the thermal treatment. Introduction of several adsorbates : CH3OH, (CH2)2SO, CH3NO2, CH3CN, C2H4, CO, NH3 and C2H5N on the surfa ce of the Cu/MgF2 preparations does not seem to modify the coordinatio n spheres of the cupric ions.