G. K. Parygina

Synthesis and study of the electronic structure of molybdenum tetrasulfide and its lithium intercalates

An X-ray amorphous phase of molybdenum tetrasulfide with the analytical formula MoS4 has been sythesized. Quantum chemical modeling of the suggested local structure of MoS4 and EHT calculation of the electronic structure of the basic (Mo2S4)4+ fragment are reported. The electronic structure of molybdenum tetrasulfide and its lithium intercalates was investigated by X-ray emission and X-ray photoelectron spectroscopy. It is shown that the change in the electronic structure of the starting molybdenum tetrasulfide to four lithium atoms per formula unit in the intercalate may be considered in the rigid band model.

X-ray emission and X-ray photoelectron study of the electronic structure of polymeric cubanocluster compounds Re4−xMoxS4Te4

The electronic structure of cubanocluster compounds of the series Re4−xMoxS4Te4 was studied by X-ray emission and X-ray photoelectron spectroscopy. The electronic structure of the (Re4S4)8+ cluster was calculated by the EHT method. It is shown that replacement of rhenium atoms by molybdenum atoms leads to changes both in the chemical bonds of the Re4S4 cubanocluster fragment and in the bond of the latter with the Te4 fragment.

X-ray photoelectron, emission, and absorption studies of the electronic structure of molybdenum and tungsten trisulfides and their intercalates

The electronic structure of molybdenum and tungsten trisulfides and their lithium intercalates is investigated by X-ray emission, absorption, and photoelectron spectroscopy. The electron density of lithium atoms intercalated into molybdenum and tungsten trisulfides is distributed over both the metal and sulfur atoms, with more over the atoms of the disulfide pair. These compounds are assumed to have an additional donor-acceptor bond involving a lone pair of disulfide sulfur atom electrons and the vacant levels of the metal. A qualitative scheme of the electronic structure of MoS3 is constructed based on experimental results and assuming the presence of a donor-acceptor bond.

X-ray emission and X-ray photoelectron studies of the electronic structure of the polymeric cubane cluster compounds Mo4S4Cl4, GaMo4S8, and GaMo4S4Te4

X-ray emission and X-ray photoelectron spectroscopy was used to study the electronic structures of the polymeric cubane cluster compounds Mo4S4Cl4, GaMo4S8, and GaMo4S4Te4. It is revealed that the ligand orbitals make significant contributions to the highest occupied molecular orbitals (M−M bonds). Substitution in the series Cl−S−Te increases the covalence of the metal—bridging ligand bonds. The experimental spectra allowed the construction of a qualitative scheme of the electronic structure of Mo4S4Cl4.

Study of the electronic structure of polymeric cubane cluster compounds Mo4S4Cl4, GaMo4S8, and Ga4Mo4S4Te4 by X-ray electron and emission spectroscopy

Abstract The electronic structure of polymeric cubane cluster compounds Mo 4 S 4 Cl 4 , GaMo 4 S 8 , and GaMo 4 S 4 Te 4 has been studied by X-ray electron and emission spectroscopy. The results of the investigation revealed that the higher occupied levels (Mo–Mo bonds) contain mainly the d-orbitals of metal atoms and include also an appreciable contribution from the ligand orbitals. Upon substitution of Cl by S or Te the covalency of the metal-bridging ligand bonds is increased. Group theory analysis of orbital interactions in Mo 4 S 4 Cl 4 has been performed. A comparison of the results of this analysis and the experimental data shows that the M–S and M–X bonds are many-centered in nature. Based on the experimental data obtained a qualitative model of the electronic structure of the valence band has been proposed.

SYNTHESIS AND INVESTIGATION OF THE ELECTRONIC STRUCTURE OF MOLYBDENUM TETRASULFIDE AND ITS LITHIUM INTERCALATES

An X-ray amorphous phase of molybdenum tetrasulfide with the analytical formula MoS4 has been sythesized. Quantum chemical modeling of the suggested local structure of MoS4 and EHT calculation of the electronic structure of the basic (Mo2S4)4+ fragment are reported. The electronic structure of molybdenum tetrasulfide and its lithium intercalates was investigated by X-ray emission and X-ray photoelectron spectroscopy. It is shown that the change in the electronic structure of the starting molybdenum tetrasulfide to four lithium atoms per formula unit in the intercalate may be considered in the rigid band model.

COMPARATIVE STUDY OF THE ELECTRONIC STRUCTURE OF Bi-SYSTEMS 2212

The electronic structure of conducting and nonconducting forms of Bi2Sr2CaCu2O8+x ceramics was investigated by X-ray and X-ray photoelectron spectroscopy. The conducting form differs in structure from the nonconducting one by the presence of oxygen and bismuth atoms in two oxidation states as well as by pd-hybridization of O2p- and Cu3d-electrons in the valence band.