THE STRUCTURE AND CATALYTIC PROPERTIES OF COORDINATION POLYHEDRA OF 3D-METALS IN METAPHOSPHATE MELTS

By EAS and ESR spectroscopy, oxygenated complexes of d-metals have bee n established in high-temperature melts NaPO3-Cr2O3-O-2 and NaPO3-CoO- O-2 and others of the type M(PO3)(x)O-2, where M is Cr, Co, V, and the ir structure has been established. The O-18/O-16 exchange reaction in the NaPO3-V2O5-O-2 melt has been studied by mass spectrometry both in the presence of the oxidized substrate and in its absence. A general a pproach has been proposed explaining the interaction between polyphosp hate complexes of 3 d-metal ions and molecular oxygen and the oxidatio n ability of the oxygenated complexes in terms of the MO theory. It ha s been established three types of interaction between 3 d-metal ions a nd molecular oxygen: donor, acceptor and donor-acceptor ones. Oxygenat ed complexes of the ions of the midle of the 3 d-element series (d(4)- d(7)) were found to possess the revealed ''partial'' oxidation ability towards alkanes.