- Structure of thallium(III) chloride, bromide, and cyanide complexes in aqueous solution
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The structures of the hydrated thallium(III) halide and pseudohalide complexes, [TlXn(OH2)m](3-n)+, X = Cl, Br, CN, in aqueous solution have been studied by a combination of X-ray absorption fine structure spectroscopy (XAFS), large-angle X-ray scattering (LAXS), and vibrational spectroscopic (Raman and IR) techniques including far-infrared studies of aqueous solutions and some solid phases with known structures. The vibrational Tl-X frequencies of all complexes are reported, force constants are calculated using normal coordinate analysis, and assignments are given. The structural results are consistent with octahedral six-coordination for the cationic complexes Tl(OH2)63+, TlX(OH2)52+, and trans-TlX2(OH2)4+. The coordination geometry changes to trigonal bipyramidal for the neutral TlBr3(OH2)2 complex and possibly also for TlCl3(OH2)2. The TlX4- complexes are all tetrahedral. Higher chloride complexes, TlCl5(OH2)2- and TlCl63-, are formed and have again octahedral coordination geometry. For the first and second halide complexes, TlX(OH2)52+ and TlX2(OH2)4+, no lengthening was found of the Tl-X bonds, with Tl-Br distances of 2.50(2) and 2.49(2) ?, respectively, and Tl-Cl distances of 2.37(2) ? for both complexes. The mean Tl-O bond distances increase slightly, ≈0.04 ?, from that of the Tl(OH2)63+ ion, at the formation of the first thallium(III) halide complexes. A further, more pronounced lengthening of about 0.1 ? occurs when the second complex forms, and it can be related to the relatively high bond strength in the trans-XTlX entity, which also is manifested through the Tl-X stretching force constants. For the recently established Tl(CN)n(3-n)+ complexes with no previously available structural information, the Tl-C distances were determined to be 2.11(2), 2.15(2), and 2.19-(2) ? for n = 2, 3, and 4, respectively. The Tl(CN)2+ complex has a linear structure, and the Tl(CN)4- complex is tetrahedral with the CN- ligands linearly coordinated. The lower complexes (n = 1-3) are hydrated, although the coordination numbers could not be unambiguously determined. A well-defined second coordination sphere corresponding to at least eight water molecules at a Tl-OII distance of ≈4.3 ? was found around the second complex, probably trans-Tl(CN)2(OH2)4+. The third cyano complex is probably pseudotetrahedral, Tl(CN)3(OH2). The bonding in the hexahydrated Tl3+ and Hg2+ ions is discussed, and differences in the mean M-O bond lengths, determined by the LAXS and EXAFS techniques, are interpreted as being due to an occurrence of two different sets of M-O distances in the first hydration shell.
- Blixt, Johan,Glaser, Julius,Mink, Jànos,Persson, Ingmar,Persson, Per,Sandstr?m, Magnus
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- Formation, equilibrium properties and decomposition in aqueous solution of monoorganothallium(III) ions containing RC(O)CH2 groups. Preparation of monoacetonylthallium(III) compounds
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The reactions of thallium(III) with some ketones in the presence and absence of Cl-, Br-, CN-, CH3COO-, and CF3COO- ions in acidic aqueous solutions, and the stabilities of the resulting monoorganotha
- Gyoeri, Bela,Sanchez, Augustin,Glaser, Julius
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- Synthesis, characterisation and structures of thio-, seleno- and telluro-ether complexes of indium(III) halides
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The indium(III) halo-bridged octahedral dimers [InX2(L-L)(μ- X)2InX2(L-L)] (X = Cl: L-L = MeS(CH2) 2SMe, MeSe(CH2)2SeMe, nBuSe(CH 2)2Sen/su
- Gurnani, Chitra,Jura, Marek,Levason, William,Ratnani, Raju,Reid, Gillian,Webster, Michael
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p. 1611 - 1619
(2009/05/30)
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- Organothallium halides
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When TlCl3 was reacted with cHexMgCl in THF, the triorganothallane TlcHex3 (1) could be obtained. The reaction of TlCl3 with PhLi in Et2O solution at 0 °C gave after workup the insoluble colorless solid Ph2TlCl (2). 2 was refluxed in pyridine. During cooling of the hot suspension colorless small crystals of [Ph2Tl(Py)2Cl]n (3) were formed. TlMes3 and TlCl3 in the molar ration 2:1 reacted in toluene at 20 °C to give the salt (TlMeS2)-[MesTlCl3] (4). The treatment of TlBr with MesMgBr solution (molar ratio 2:1) in THF/toluene lead to a suspension of MeSTlBr2 and Tl. The suspension was refluxed in pyridine. After cooling of the solution, colorless crystals of [MesTlBr2(Py)2]·Py (5) could be isolated. I and 3-5 were characterized by NMR and MS techniques and in the case of 3 by vibrational spectroscopy. In addition X-ray structure determinations of 3-5 were performed. According to this the structure of 3 can be understood in two ways: 3 consists of polymeric linear chains along [001] buildt-up by square planar [TlPh 4]- and [Tl(Py)4]3+ units connected by Cl- ions. This would mean a description as [{TlPh 4Cl}{Tl(Py)4CI}]n. The disorder phenomena in 3 would allow the second explanation, the formation of chains [Ph 2Tl(Py)2Cl]n. The unit cell of 4 contains zig-zag chains of four-membered rings consisting of linear (TlMes 2)+ units and distorted tetrahedrons of [MesTlCl 3]- ions. All chloro ligands in 4 are μ-bridging forming Tl2Cl2 four-membered rings and Tl-Cl-Tl sequences. In 5, molecular units of [MeSTlBr2(Py)2] are present. The thallium atoms possess a trigonal bipyramidal environment.
- Kuzu, Istemi,Neumueller, Bernhard
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p. 1524 - 1530
(2008/10/09)
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- Reactivity of Sulphuryl Chloride in Acetonitrile with the Elements
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Sulphuryl chloride in MeCN reacts with all but the most refractory elements to give mainly solvated chlorides at or below 300 K in contrast with SO2Cl2 alone which requires at least twice this temperature.There is evidence for an ionic mechanism based on analogy, thermochemistry, transport measurements and additive effects.The instability of these solutions leading to polymerization, together with its inhibition, is described.Sulphur dioxide formed in reactions seldom plays a reductive role apart from influencing formation of the mixed-valence Tl4Cl6.Semiquantitative kinetic measurements in different solvents emphasize the uniqueness of MeCN.For most elements attack is diffusion controlled across surface films giving a parabolic dependence on time which can be linearized if film growth is prevented by changing the solvent mix.The varied nature of these surface films vitiates any simple relation between rate and periodicity.Some applications are indicated.
- Woolf, Alfred A.
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p. 3325 - 3330
(2007/10/02)
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- Chromium(VI) Oxidation of Thallium(I) in Aqueous Acetic Acid and Effect of Added Vanadium(V) on the Reaction
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Chromium(VI) oxidation of thallium(I) in 60percent acetic acid containing 1.25 mol dm-3 hydrochloric acid is a second order reaction, understood to be between CrO3Cl(-) and TlCl.Increase in and accelerates the reaction.Added V(V) accelerates the reaction till slightly exceeds because of a 1:1 interaction between V(V) and Tl(I).At higher , the rate constant is lowered due to a specific cation effect.No interaction between added V(V) and Tl(I) is encountered in the case of the reaction in 40percent aqueous acetic acid; however, in 80 and 90percent aqueous acetic acid, 2:3 and 1:2 interactions between V(V) and Tl(I) are observed.
- Gokavi, G. S.,Raju, J. R.
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p. 494 - 497
(2007/10/02)
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