7784-36-3Relevant articles and documents
Synthesis and Raman spectra of [Nd (XeF2)n](AsF6)3 (n = 3, 2.5) and crystal structure of [Nd (XeF2)2.5](AsF6)3
Tramsek,Lork,Mews,Zemva
, p. 243 - 249 (2001)
The reaction between Nd(AsF6)3(solv) and excess of XeF2(solv) in anhydrous HF (aHF) yields compounds of the type [Nd(XeF2)n](AsF6)3 (n = 3, 2.5). The first compound is very soluble in aHF while the latter crystallizes from the saturated solution in aHF. Pink needles [Nd(XeF2)2.5] (AsF6)3 crystallize in the space group C2/m with a = 3463.7(8) pm, b = 586.3(2) pm, c = 1010.7(2) pm, β = 103.53(2)°, V = 1.9955(9) nm3, Z = 4, R1 = 0.0379, wR2 = 0.0910, 5341 reflections collected, 2318 independent reflections. The Nd center is coordinated by a tricapped trigonal prism of nine fluorine atoms. The rectangular faces are capped by three coordinated XeF2 molecules. The regular trigonal prisms are formed by six different edge-bridging AsF6 octahedra, connecting the Nd centers to infinite chains. Two of such chains are interconnected by one of the XeF2 molecules forming a double chain.
Syntheses, characterization, and computational study of AsF5 adducts with ketones
Stuart, Daniel,Wetmore, Stacey D.,Gerken, Michael
, p. 9 - 16 (2019)
Lewis acid-base adducts between AsF5 and the ketones, acetone, cyclopentanone, and adamantanone, were synthesized from SO2 and CH2Cl2 solutions. These adducts, which contain O—As pnictogen bonding interactions, were found to be stable in solutions at room temperature. Raman and NMR spectroscopy of the solid adducts showed a characteristic decrease in the C=O stretching frequency, as well as dramatic deshielding of the 13C resonance of the carbonyl group upon adduct formation. Fluorine-19 NMR spectroscopy showed the two fluorine environments of the O–AsF5 moiety. Optimization of the gas-phase geometry using DFT calculations yielded geometries with essentially planar CC=OAs moieties. NBO analyses of the adducts and the free ketones show the polarization of the C=O bond upon adduct formation. The lowering of the LUMO energies upon adduct formation is more dramatic than what was found for protonation of ketones and reflects the substantially enhanced electrophilicity of the adducted ketones.
[Li(XeF2)n](AF6) (A = P, As, Ru, Ir), the first xenon(II) compounds of lithium. Synthesis, Raman spectrum, and crystal structure of [Li(XeF2)3](AsF6)
Tavcar, Gasper,Zemva, Boris
, p. 4319 - 4323 (2013/05/22)
The reactions between compounds of the type MAF6 (M = alkali metal; A = P, As, V, Ru, Ir, Sb, Nb, Ta) and xenon difluoride were studied in anhydrous hydrogen fluoride solvent. The coordination products [M(XeF 2)n]AsF6 were only observed in the case of LiAF6 (A = P, As, Ru, Ir), and the crystal structure of [Li(XeF 2)3]AsF6 was determined (monoclinic space group P21 with a = 6.901(9) A, b = 13.19(2) A, c = 6.91(1) A, β = 91.84(2), and Z = 2). The coordination sphere of lithium is comprised of six F atoms. The compound series was also characterized by Raman spectroscopy.
Palladium chemistry in anhydrous HF/AsF5 superacid medium
Mazej, Zoran,Benkic, Primoz,Tressaud, Alain,Zemva, Boris
, p. 1827 - 1834 (2007/10/03)
Pd metal dissolves in anhydrous HF (aHF) acidified with AsF5 in the presence of F2 at ≈298 K to give a blue-green solution from which green Pd(AsF6)2 can be isolated. The latter was also prepared by the interaction of PdF2 and AsF5 in aHF or by the reaction between PdO and F2 in aHF acidified with AsF 5. Powdered Pd(AsF6)2 slowly loses AsF 5 in a dynamic vacuum. It can therefore be isolated from solution at T 6)2 were prepared by solvothermal synthesis from a Pd/AsF5/F2/aHF mixture at 393 K. Pd(AsF6)2 is triclinic with a = 500.9(5), b = 538.3(5), c = 864.9(9) pm, α = 74.46(3), β = 89.97(4), γ = 62.47(2)° V = 0.1972(3) nm3, and Z = 1, space group P1 (No. 2). The six-coordinate Pd atoms (coordinated with fluorine) are well separated by isolated AsF6 units. In the 2-175 K temperature range Pd(AsF 6)2 follows the Curie-Weiss law with μeff = 3.53 B.M., Tn = 8 K and θp = -13 K. Because of cation-anion interactions, the AsF6- anions deviate from ideal Oh symmetry. The reduced symmetry can be seen in vibrational spectra, where splitting of the anion vibrational modes can be observed. The oxidation of Pd metal or PdO with F2 in neutral aHF yielded Pd 2F6. No reaction was observed between Pd, PdO or Pd 2F6 and AsF5 in aHF. All attempts to prepare PdFAsF6 were unsuccessful. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
