Publications by authors named "Alexander M Fedoseev"

Five new mixed-valence Np/An molybdates of the composition [C(NH)][(NpO)(NpO)(MoO)(HO)]·HO (), [C(NH)][(NpO)(NpO)(MoO)(HO)]·3HO (), Na[(NpO)(PuO)(MoO)(HO)]·HO (), Na[(NpO)(UO)(MoO)]·13HO (), and LiNa[(NpO)(NpO)(MoO)(HO)]·4HO () have been synthesized and structurally characterized. The coordination polyhedra of the Np and An atoms in compounds - are pentagonal bipyramids. The basis of structures - is anionic layers of the composition [(NpO)(AnO)(MoO)(HO)].

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In this work, we have proposed two new methods for the synthesis of [TcOL] (where L = imidazole (Im), methylimidazole (MeIm)) complexes using thiourea (Tu) and Sn(II) as the reducing agents. The main and by-products of the reactions were determined, and possible reaction mechanisms were proposed. We have shown that the reduction of Tc(VII) with thiourea is accompanied by the formation of the Tc(III) intermediate and further oxidation to Tc(V).

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[H O ] [Tc O ] ⋅ 4H O [1] was prepared from an aqueous Tc O solution concentrated over anhydrous H SO . [Tc O ] is the first polyanionic species to be reported for Tc. The unit cell contains one centrosymmetric [Tc O ] polyanion as well as hydronium ions and water molecules.

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New complexes of neptunyl(V) isothiocyanate with 4'-aryl-substituted 2,2':6',2″-terpyridines (Terpy) and ,-dimethylacetamide (DMA) were obtained: [(NpO)(4'-Ph-Terpy)(DMA)(NCS)]·DMA, [(NpO)(4'-(4-(CF)CH)-Terpy)(DMA)(NCS)]·2HO·DMA, [(NpO)(4'-(3-BrCH)-Terpy)(DMA)(NCS)]·DMA, and [(NpO)(4'-(2-(COOH)CH)-Terpy)(DMA)(NCS)]·DMA. The structures of the compounds were determined with X-ray diffraction analysis. The neptunium coordination polyhedra were found to be pentagonal bipyramids with O atoms of the NpO groups in the apical positions and the equatorial planes formed by three N atoms of the terpyridine ligand, a N atom of the isothiocyanate anion, and an O atom of DMA.

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