Synthesis and Structure of Triphenylbismuth Dinitrite and Dinitrate

Triphenylbismuth dinitrate (I) and triphenylbismuth dinitrite (II) were synthesized through the reaction of triphenylbismuth dichloride with silver nitrate in an acetone–alcohol (1 : 1) solution or with sodium nitrite in acetone–water (1 : 1) solution. According to X-ray diffraction data, bismuth atoms in Iand II have a distorted trigonal bipyramidal configuration. The intramolecular Bi···N(1,2) contacts in II (2.997(3), 2.982(4) Å) are shorter than similar contacts in I(3.038(3), 3.031(3) Å); the Bi···O(2,4) distances in II and Bi···O(2,5) distances in I are equal to 2.879(2), 2.913(3) and 2.893(3), 2.896(3) Å, respectively.     

Synthesis and Structure of Bismuth Tris(3-Methylbenzoate) [Bi(O2CC6H4CH3-3)3]∞ and Phenylbismuth Bis(3,4,5-Trifluorobenzoate) [PhBi(μ-O2CC6H2F3-3,4,5)(O2CC6H2F3-3,4,5)]2

Bismuth tris(3-methylbenzoate) [Bi(O₂CC₆H₄CH₃-3)₃] (I) and phenylbismuth bis(3,4,5-trifluorobenzoate) [PhBi(-O₂CC₆H₂F₃-3,4,5)(O₂CC₆H₂F₃-3,4,5)]₂ (II) were synthesized by reacting triphenylbismuth with 3-methylbenzoic and 3,4,5-trifluorobenzoic acids. Coordination numbers of bismuth atoms in I and II are 9 and 6, respectively; carboxylate ligands function as bi- and tridentate ligands. The Bi-O distances in compound I vary in the range of 2.218(3)-3.202(4) Å. The Bi-O and Bi-C bond lengths in II are 2.301(2)-2.674(2) and 2.223(3) Å, respectively.     

Synthesis and complex investigation of potassium ammonium hexafluorozirconates: I. Synthesis and X-ray diffraction study of K2-x (NH4)xZrF6 (0 < x < 2) crystals

The synthesis and X-ray diffraction study of compounds K_2-x (NH₄)xZrF₆ (0 < x < 2) were carried out. In all crystals of mixed composition, potassium cations are isomorphously replaced by ammonium cations. The compounds with x < 0.5 are isostructural to K₂ZrF₆ and those with x > 1.5, to (NH₄)₂ZrF₆. At 0.5 < x < 1.5, the structures are built of linear polymeric chains formed by edge-sharing Zr dodecahedra. The distribution of potassium and ammonium cations over the cationic positions was considered.     

Combined Activation of Anthracite

The effect of anthracite pretreatment on the production of activated carbons and increase in the specific porosity of the resulting adsorbent was studied.     

Effect of Thermochemical Treatment of Anthracite on Its Activation by Steam

The effect of thermochemical treatment of anthracite, including its oxidation, impregnation with a solution of a compound of an alkali metal, and heat treatment in an inert gas atmosphere on the subsequent activation of the material with steam was studied. It was shown that such treatment of anthracite leads to considerable improvement at the final stage of the production of active carbon; there is an increase (of almost three times) in the rate of activation (burn off) of the anthracite and better pore formation compared with the technology involving direct activation with steam.     

Formation of the heteropolynuclear complex ([NH2(C4H9)2][Au{S2CN(C4H9)2}2][CdCl4])n during the chemisorption of gold(III) with cadmium dibutyldithiocarbamate: Structure and thermal properties

The chemisorption properties of cadmium dibutyldithiocarbamate with respect to [AuCl₄]⁻ in 2M HCl solutions are studied. The heterogeneous reaction of gold(III) binding affords the heteropolynuclear compound ([NH{₂(C₄H₉)₂][Au{S₂CN(C₄H₉)₂}₂][CdCl₄]) _n (I). The molecular and crystal structures of compound I are determined from the X-ray diffraction data. Each of three ions is presented in the structure by two conformers. The irreversible decomposition of some dibutyldithiocarbamate groups is observed during the chemisorption of gold(III), which noticeably decreases the efficiency of gold binding with the sorbent studied and its sorption capacity. The study of the thermal properties of compound I shows that gold(III) is reduced to the metal during thermolysis.     

Polymeric thallium(I) O,O′-diisopropyl dithiophosphate [Tl{S2P(O-iso-C3H7)2}]n: Synthesis, structure, and 13C and 31P CP/MAS NMR spectra

The crystalline polymeric thallium(I) O,O′-diisopropyl dithiophosphate [Tl{S₂P(O-iso-C₃H₇)₂}] _n (I) was obtained and examined by solid-state ¹³C and ³¹P CP/MAS NMR spectroscopy. Diagrams of the χ² statistic were constructed from the complete ³¹P MAS NMR spectra and used to calculate the ³¹P chemical shift anisotropy (δ_aniso = (δ _zz − δ_iso)) and the asymmetry parameter (η = (δ _yy − δ _xx )/(δ _zz − δ_iso)). The ³¹P chemical shift tensor has a nearly axial symmetry (η = 0.22, δ _zz < δ _yy ≈ δ _xx ). The MAS NMR spectral patterns correspond to the negative sign of δ_aniso (δ _zz < δ _yy < δ _xx ), which indicates bridging or chelating-bridging coordination of the dithiophosphate ligands (Dtph). X-ray diffraction analysis revealed a polymeric structure of compound I. The polymer chain consists of alternating mononuclear [Tl{S₂P(O-iso-C₃H₇)₂}] molecules with opposite spatial orientations. The Dtph ligands are coordinated in a mixed, chelating-μ₃-bridging fashion. The shape of the ³¹P NMR signal was interpreted in terms of the ³¹P-^203,205Tl coupling pattern proposed from crystallographic data.