14693-81-3Relevant academic research and scientific papers
Well-ordered crystals of TaI5. The formation of the ternary iodide CsTaI6
Habermehl, Katja,Pantenburg, Ingo,Held, Peter,Meyer, Gerd
, p. 829 - 831 (2008)
Well ordered single crystals of TaI5 (orthorhombic, Pnma (no. 62), a = 1396.2(2), b = 2009.5(4), c = 660.7(1) pm, Z = 8, R1 for 967 reflections with I02σ(I0): 0.0381) were obtained from a reaction of the elements. The structure determination confirms Mueller's prediction of 1978. Single crystals of CsTaI6 (monoclinic, C2/c (no. 15), a = 1362.3(2), b = 709.9(1), c = 1736.2(3) pm, β = 128.77(1)° , Z = 4, R1 for 1140 reflections with I 02σ(I0): 0.0378) were obtained by the oxidation of tantalum with CsI3. Both crystal structures contain [TaI6] octahedra which are edge-connected to Ta2I10 dimers in TaI5 and isolated as [TaI6]- anions in the salt Cs[TaI6] (CsWCl6 type of structure).
Synthesis and structure of Ta4SI11: Disorder and mixed valency in the first tantalum sulfide iodide
Smith, Mark D.,Miller, Gordon J.
, p. 4165 - 4170 (2003)
The new compound Ta4SI11 has been prepared by direct reaction of the elements at 430 °C for 2 weeks in evacuated Pyrex ampules and characterized by single-crystal x-ray diffraction, x-ray photoelectron spectroscopy, magnetic susceptibility measurements, and semiempirical electronic structure calculations. Ta4SI11 crystallizes with orthorhombic symmetry in space group Pmmn; a = 16.135(3) A, b = 3.813(1) A, c = 8.131(2) A, and Z = 1. The disordered structure involves two crystallographically distinct sites for Ta atoms, both of which are 50% occupied as well as a bridging anion site that is 50% S and 50% I. Magnetic susceptibility above 100 K gives μeff = 1.53 μB to suggest one unpaired electron per formula unit. x-ray photoelectron spectroscopy and extended Hueckel calculations suggest that the structure consists of Ta3 triangles and isolated Ta atoms, leading to the formulation (Ta3)9+(Ta4+)(S2-) (I-)11 and we hypothesize that each Ta3 is capped by a sulfur atom.
Heavier Halides of Early Transition Elements by Halide-exchange Reactions. Crystal and Molecular Structure of2
Calderazzo, Fausto,Pallavicini, Piersandro,Pampaloni, Guido,Zanazzi, Pier Francesco
, p. 2743 - 2746 (2007/10/02)
The decahalogenodimetalates of zirconium(IV) as their triphenylmethyl deivatives have been obtained by the reaction of M(BH4)4 with the appropriate Ph3CX or by addition of Ph3CX to MX4.The crystal and molecular structure of2 h
Chemistry of polynuclear metal halides. I. Preparation of the polynuclear tantalum halides Ta6X14
Kuhn, Phyllis J.,McCarley, Robert E.
, p. 1482 - 1486 (2008/10/08)
The anhydrous halides (Ta6X12)X2 (X = Br, I) have been produced in good yields by the reduction of the tantalum(V) halides with aluminum foil in a temperature gradient according to the reaction 18TaX5(g,l) + 16Al(s) = 3(Ta6X12)X2(s) + 16AlX3(g,l). Final products having atom ratios X/Ta smaller than the calculated 2.33 were shown to contain some tantalum metal. A lower tantalum chloride mixture was prepared by the same procedure, but evidence indicated the principal phase present was TaCl2.5 (Ta6Cl15). However, good yields of the ion Ta6Cl122+ could be obtained in solution from the anhydrous solids. Reflectance spectra of the anhydrous solids and absorption spectra of aqueous solutions were determined. The spectra were found to exhibit bands very characteristic of the Ta6X122+ structure.
The preparation of tantalum(IV) bromide, tantalum(IV) iodide, and pyridine adducts of the tantalum(IV) halides
McCarley,Boatman
, p. 547 - 551 (2008/10/08)
The necessary conditions for preparation of TaBr4 and TaI4 by reduction of the pentahalides with tantalum or aluminum metal in a sealed tube under a controlled temperature gradient have been demonstrated. An unusual, but more fruitful synthesis of TaI4 was devised from the reduction of TaI5 with pyridine. X-Ray powder patterns of diamagnetic, isomorphous TaCl4 and TaBr4 were indexed on an orthorhombic unit cell of dimensions a = 8.10, b = 8.92, c = 6.80 ?. and a = 8.58, b = 9.30, c = 7.21 ?., respectively. The compounds TaCl4(C5H5N)2 and TaBr4(C5H5N)2 were prepared by the reaction of pyridine with the respective tetrahalides at room temperature. Unusually low magnetic moments of 0.69 and 0.43 B.M. were found for the chloride- and bromide-pyridine adducts, respectively.
