I. N. Ivleva

Nature of satellites in x-ray photoelectron spectra XPS of paramagnetic cobalt (II) compounds

Abstract XPS spectra of a number of paramagnetic Co(II) compounds are studied and the correlation between the intensity of the Co 2p 3 2 satellite and the magnitude of its magnetic moment is shown. A new approach is put forward to explain the experimental data.

Interaction of triethylaluminium with acetylacetonates of transition metals

Abstract The reaction of AlEt 3 with acetylacetonates of Cr III , Fe III , Co III , Ni II and Pd II in benzene and cyclohexane has been studied in a wide range of initial ratios of AlEt 3 /M(acac) n . Quantitative analysis of the reaction mixture, performed with the help of UV spectra, showed that acetylacetonate ligands were transferred from the transition metals to aluminium. A scheme involving stepwise substitution of ethyl radicals by acetylacetonate ligands on AlEt 3 with further formation of an Al(acac) 3 -Et 2 Al(acac) mixture is proposed for Al/M n (M = Fe, Co, Ni). An increase of the Al/M ratio causes an increase of the Et 2 Al(acac) fraction. The only reaction product containing an acetylacetonate ligand is Et 2 (Al(acac) at Al/M = n . Cr(acac) 3 and Pd(acac) 2 interact with AlEt 3 forming Et 2 Al(acac) at any initial ratio of Al/M. Stabilization of intermediate organo-nickel and -palladium compounds has been observed in the interaction of AlEt 3 with Pd(acac) 2 and Ni(acac) 2 in benzene, which inhibited the reaction rate considerably. Magnetochemical measurements showed that Fe III , Co III , Ni II were reduced to the zerovalent state in their reaction with AlEt 3 (Al/Mn ⩾ n ). The content of the finely dispersed metal component is negligible small and the greater part of transition metal is present as M 0 complexes, where Et 2 Al(acac) formed in the reaction is the main stabilizing ligand.

Isolation of a new intermediate complex in the nitrogen-fixing system (π-C5H5)2TiCl + MeMgI + N2

A binuclear complex cp2TiN2Ticp2 has been isolated at low temperature in the system cp2TiCI + MeMgI + N2(cp =π-C5H5); it is apparently a di-imide derivative, and initially froms N2H2 when decomposed with HCl.

Temperature effects in x-ray photoelectron spectra of paramagnetic cupric and iron complexes with anomalous magnetic properties

Abstract The temperature dependence of the XPS spectra of paramagnetic cupric and iron complexes with anomalous magnetic properties is studied. It was found that the XPS spectra of polynuclear complexes with antiferromagnetic interaction, such as cupric acetate, do not change with temperature, although their magnetic moments diminish essentially. The Fe 2p spectra of mononuclear iron (III) complexes with the spin multiplicity transitions S = 1 2 ⇌ S = 5 2 exhibit temperature-dependent reversible alterations of shake-up satellite intensity which correlate with the spin state of the paramagnetic Fe(III) ion. The results obtained prove the mechanism of appearance of intensive shake-up satellites in XPS spectra of paramagnetic 3d element complexes, which relates shake-up excitations with the interaction of the photoelectron with unpaired valence 3d electrons during photoionization.

Isolation and investigation of the complex Li3[FeNp3N2]·nEt2O - the product of interaction of molecular nitrogen with a naphthyl derivative of zero-valent iron

Abstract The complex Li3[FeNp3N2]·nEt2O produced by the reaction of N2, with Li3FeNp3·mEt2O has been isolated and its magnetic properties and IR spectra investigated. The proposed structure of the complex includes the linear fragment FeNNLi.

Kinetics of toluene hydrogenation over platinum-titania catalysts in conditions of strong metal-support interaction

Toluene hydrogenation was investigated over different platinum-titania catalysts. It was found that the form of kinetic equation of the reaction does not depend on the modifications of titania (rutile, anatase) but the catalyst activity is different. The catalyst reduction at temperature higher than 300oC leads to strong metal-support interaction (SMSI) which is manifested in a decrease of the reaction rate.

Formation of propylene in the reaction of methane with acetylene on a NiOx/BN heterogeneous catalyst

Reaction of methane with acetylene in the presence of a heterogeneous NiOx/BN catalyst in the temperature range 300–450‡C results in the formation of propylene (1% yield). Using13CH4 it was found that propylene arises both as a product of acetylene conversion and as a hydromethylation product of C2H2 with methane. The ratio of heavy and light C3H6 in the product mixture was 1∶4.

Magnetic susceptibility and x-ray photoelectronic spectra of CoO-MgO solid solutions

Employing the magnetic susceptibility and x-ray photoelectronic spectroscopy methods it was shown that the high values of the Co(II) magnetic moments in a CoO-MgO solid solution in the air are due to the adsorption of oxygen in the paramagnetic form.

Hydrazine-producing intermediate in the nitrogen fixing system: cp2TiCl2+ PriMgCl + N2

An intermediate paramagnetic complex (cp2Ti)2N2MgCl has been isolated at –60 °C in the system: cp2TiCl2+ PriMgCl + N2 in ether (cp =π-C5H5); the complex forms N2H4 when decomposed by HCl.