17029-22-0Relevant academic research and scientific papers
Disproportionation of Ag(II) to Ag(I) and Ag(III) in fluoride systems and syntheses and structures of (AgF+)2AgF4-MFe6 - salts (M = As, Sb, Pt, Au, Ru)
Shen, Ciping,Z?emva, Boris,Lucier, George M.,Graudejus, Oliver,Allman, John A.,Bartlett, Neil
, p. 4570 - 4577 (2008/10/08)
Interaction of Ag+ salts in anhydrous liquid hydrogen fluoride, aHF, with AgF4- salts gives amorphous red-brown diamagnetic AgIAgIIIF4, which transforms exothermally to brown, paramagnetic, microcrystalline AgIIF2 below 0°C. AgIAuIIIF4 prepared from Ag+ and AuF4- in aHF has a tetragonal unit cell and a KBrF4 type lattice, with a = 5.788(1) A?, c = 10.806(2) A?, and Z = 4. Blue-green AgIIFAsF6 disproportionates in aHF (in the absence of F- acceptors) to colorless AgIAsF6 and a black pseudotrifluoride, (AgIIF+)2AgIIIF4 -AsF6-. The latter and other (AgF)2AgF4MF6 salts are also generated by oxidation of AgF2 or AgF+ salts in aHF with F2 or in solutions of O2+MF6- salts (M = As, Sb, Pt, Au, Ru). Single crystals of (AgF)2AgF4AsF6 were grown from an AgFAsF6/AsF5 solution in aHF standing over AgF2 or AgFBF4, with F2 as the oxidant. They are monoclinic, P2/c, at 20°C, with a = 5.6045(6) A?, b = 5.2567(6) A?, c = 7.8061(8) A?, β = 96.594(9)°, and Z = 1. The structure consists of (AgF)nn+ chains (F-Ag-F = 180°, Ag-F-Ag = 153.9(11)°, Ag-F = 2.003(4) A?), parallel to c, that enclose stacks of alternating AgF4- and AsF6-, each anion making bridging contact with four Ag(II) cations of the four surrounding chains caging them. There is no registry between the ordered array in one cage and that in any neighboring cage . The F-ligand anion bridges between the anions and, with the Ag(II) of the chains, generates a trifluoride-like structure. (AgF)2AgF4AsF6 [like other (AgF)nn+ salts] is a temperature-independent paramagnet except for a Curie tail below 50 K.
Halogen-facilitated Preparation of S4(AsF6)2*xSO2 (x a Convenient Synthesis of Se4(AsF6)2 and Se4(Sb2F11)2
Murchie, Michael P.,Passmore, Jack,Sutherland, George W.,Kapoor, Ramesh
, p. 503 - 508 (2007/10/02)
Sulfur reacted with an excess of AsF5 at room temperature in the presence of a trace amount of halogen (X2 = Cl2, Br2 or I2) or AsCl4AsF6 in SO2 to give S4(AsF6)2*xSO2 (x a few minutes.A similar, but slower, reaction with SbF5 in SO2 or AsF3 at room temperature gave quantitative yields of S4(Sb2F11)2.The vibrational spectra of these salts with tentative assignments are reported.The corresponding preparations of Se4(AsF6)2 and Se4(Sb2F11)2 are also greatly facilitated by the presence of traces of halogen.Reactions of sulfur (or selenium) with SbF5 with and without traces of X2 in SO2 designed to give M4(SbF6)2 (M = S or Se) gave products that contained M42+, an unidentified SbV fluoroanion and some SbIII-containing species.A comnparative study was made on the effect of solvent, oxidising agent and facilitating reagent on the course of reaction.Possible reaction pathways for oxidation of sulfur (or selenium) by AsF5 (or SbF5) with and without the addition of traces of X2 or AsCl4AsF6 have been proposed.
Preparations and X-ray crystal structures of iodo-cyclo-heptasulfur hexafluoroantimonate(V) and hexafluoroarsenate(V), S7ISbF6 and S7IAsF6
Passmore, Jack,Sutherland, George,Taylor, Peter,Whidden, Tom K.,White, Peter S.
, p. 3839 - 3845 (2008/10/08)
S7IAsF6 and S7ISbF6 were prepared essentially quantitatively by a variety of routes. Attempts to prepare S8I+ salts were unsuccessful. S7ISbF6 crystallizes in the orthorhombic space group P212121 with a = 11.786 (2) ?, b = 9.187 (1) ?, c = 12.400 (3) ?, and dcalcd = 2.90 Mg m-3 for Z = 4. The structure has been determined by multiple-solution direct methods and refined by least squares to final agreement indices R1 = 0.046 and R2 = 0.061 for 1628 independent reflections with I ≥ 2σ(I). S7IAsF6 crystallizes in the triclinic space group P1 with a = 15.516 (11) ?, b = 11.813 (8) ?, c = 11.650 (8) ?, α = 107.30 (4)°, β = 74.71 (5)°, γ= 104.62 (5)°, and dcalcd = 2.78 Mg m-3 for Z = 6. The structure was refined to a final agreement index R = 0.14. The S7I+ cations in both salts and in (S7I)4S4(AsF6)6 are essentially identical. S7I+ contains a seven-membered sulfur ring with a slightly twisted chair conformation, similar to that of S7, with an exocyclic iodine, and has a geometry similar to that of S7O. The sulfur-iodine bond length is 2.342 (3) ? and corresponds to a bond order of 1. The sulfur-sulfur distances within the ring vary from 1.906 (5) to 2.389 (4) ?. There is one short intracationic iodine-sulfur contact of 3.394 (3) ?. The geometry and bond length variations in S7I+ are discussed and compared with those of related systems. Some experimental observations on Sx(AsF6)2, 19 ≥ x ≥ 16, are presented and the nature of these species is discussed.
