Structure of the Dimethyl Sulfoxide Solvated Thallium(III) Ion in Solution and in the Solid State

Abstract

The structure and vibrational spectra of the dimethyl sulfoxide solvated thallium(III) ion have been studied in a dimethyl sulfoxide solution and in the solid state. X-ray crystallography shows a trigonal unit cell, space group R(-)3 (No. 148), for the [Tl(dmso)(6)](ClO(4))(3) compound with Z = 3, a = b = 11.9764(13) [11.8995(9)] A, c = 20.802(2) [20.467(2)] A, and V = 2584.0(5) [2509.9(4)] A(3) at 295 [150] K. The crystal structure comprises a highly symmetric hexakis(dimethyl sulfoxide)thallium(III) ion, with thallium in a (-)3 symmetry site and a Tl-O bond distance of 2.224(3) A at 295 K. The octahedral TlO(6) kernel is compressed along the threefold axis with an O-Tl-O bond angle of 96.20(11) degrees. The Tl-O-S bond angle of 120.7(2) degrees corresponds to a Tl.S distance of 3.292(2) A. One perchlorate ion centered on the (-)3 axis was described by a statistically disordered model. A low-temperature EXAFS study (10 K) resulted in the Tl-O and Tl.S distances of 2.221(4) and 3.282(6) A, respectively, consistent with a Tl-O-S bond angle of 120(1) degrees. The low Debye-Waller factors confirm a regular coordination without the disorder of the dimethyl sulfoxide ligands, which would have resulted from the alternative choice of space group R3 for the crystal structure. Raman and infrared spectra have been recorded and assigned, with the bands at 435 and 447 cm(-)(1) corresponding to the vibrational frequency of the symmetric and asymmetric Tl-O stretching modes, respectively. EXAFS data of a 0.5 mol dm(-3)thallium(III) trifluoromethanesulfonate in a dimethyl sulfoxide solution were consistent with that of a hexasolvated ion with mean Tl-O and Tl.S distances of 2.22(1) and 3.33(2) A, respectively, which correspond to a mean Tl-O-S bond angle of 124(2) degrees. The anomalously large disorder parameter for the Tl-O distances is consistent with a weak pseudo-Jahn-Teller effect. The (205)Tl, (13)C, and (1)H NMR spectra of the complex in solution show single signals at 1886, 39.5, and 2.3 ppm, respectively.

Dimethyl sulfoxide solvates of the aluminium(iii), gallium(iii) and indium(iii) ions. A crystallographic, EXAFS and vibrational spectroscopic studyElectronic supplementary information (ESI) available: normalized X-ray absorption edges, calculated separate contributions of the different scattering paths to the EXAFS oscillations for the dimethyl sulfoxide solvated gallium(iii) and indium(iii) ions in the solid state and solution; correlation between compression ratio (s/h) and bond lengths in [M(dmso)6]3+ c

“…16, 17 Interpretation of the vibrational spectra is also facilitated because the non-coordinated iodide ions give no additional vibrational frequencies. The strength and nature of the metal-oxygen bond and its effect on the dimethyl sulfoxide ligand has been evaluated by normal coordinate analysis and compared with other dimethyl sulfoxide solvates.…”

Synthesis and Structure of Monomeric and Platinum-Bonded (1,10-Phenanthroline)thallium Complexes

“…[2j,23] It was found that there is a correlation between the spin-spin coupling constant and the metalϪmetal separation/bond strength in the series of complexes [(NC) 5 PtϪTl(CN) n ] nϪ (n ϭ 1Ϫ3). [11] For the currently studied compounds, [(NC) 4 PtϪTl(solv)] ϩ , [(NC) 4 PtϪTl-(phen) n ] ϩ (n ϭ 1Ϫ2), and [(NC) 5 PtϪTl(phen) n ] (n ϭ 1Ϫ2), 205 Tl NMR chemical shifts are in the Tl ϩ region for [(NC) 4 PtϪTl(solv)] ϩ and between Tl I and Tl III for all the others. [6] NMR chemical shifts for heavy metals with large chemical shift ranges are very sensitive to the oxidation state of the metal ion.…”

Small Platinum−Thallium Clusters Stabilized by Ethylenediamine, [(NC)5Pt−Tl(en)n−1] (n = 1−3) − Characterization in Solution and in the Solid State

“…The studied PtϪTl complexes can thus be treated as intermediates in an overall two-electron transfer process eventually leading to thermodynamically stable products in the stable oxidation states Pt IV and Tl I . [9,10] Another indication of the changed oxidation states of the metals in these compounds is provided by the bond lengths TlϪO [23] and [Tl(en) 3 ] 3ϩ (average 2.370 Å ). [16] The slight increase of the bond lengths, despite the lower coordination number in the studied PtϪTl compounds, is compatible with the change of the oxidation states of the metal ions upon formation of the PtϪTl bond.…”