Striking stability of a mixed-valence thallium(III)-thallium(I) complex in some solvents
(2023) In Journal of Molecular Liquids 385.- Abstract
At the dissolution of solid anhydrous thallium(III) trifluoromethanesulfonate, Tl(CF3SO3)3, or thallium(III) trifluoroacetate, Tl(CF3COO)3, in dimethylsulfoxide (dmso) or N,N,N’,N’-tetramethylurea (tmu), intensely red-colored complexes are formed. This red thallium complex is stable for years in dmso, while it is reduced fairly rapidly to thallium(I) in tmu with a half-life time of an hour. At the dissolution of Tl(CF3SO3)3 in N,N-dimethylpropyleneurea (dmpu) an immediate reduction to thallium(I) takes place. A stable colorless aqueous thallium(III) solution is obtained at the dissolution in acidic water. Stable dmso solutions and solid dmso solvates... (More)
At the dissolution of solid anhydrous thallium(III) trifluoromethanesulfonate, Tl(CF3SO3)3, or thallium(III) trifluoroacetate, Tl(CF3COO)3, in dimethylsulfoxide (dmso) or N,N,N’,N’-tetramethylurea (tmu), intensely red-colored complexes are formed. This red thallium complex is stable for years in dmso, while it is reduced fairly rapidly to thallium(I) in tmu with a half-life time of an hour. At the dissolution of Tl(CF3SO3)3 in N,N-dimethylpropyleneurea (dmpu) an immediate reduction to thallium(I) takes place. A stable colorless aqueous thallium(III) solution is obtained at the dissolution in acidic water. Stable dmso solutions and solid dmso solvates of thallium(III) perchlorate, nitrate and trifluormethanesulfonate can be prepared by adding dmso to concentrated acidic aqueous thallium(III) solutions. These experimental observations conclude that the pure solids Tl(CF3SO3)3 and Tl(CF3COO)3 play an essential role in the formation of the red-colored thallium complexes. 205Tl NMR data show that the red thallium complex contains equal amounts of thallium(III) and thallium(I). The structure of the red thallium complex in dmso, as determined by EXAFS, has Tl–O bond distances of 2.216(3) and 2.80(2) Å, which are in very close agreement with the bond distances obtained in the pure dmso solvates of the thallium(III) and thallium(I) ions, respectively, and a Tl···Tl distance of 3.49(1) Å bridged by oxygen atoms. From the EXAFS data it is impossible to distinguish if dmso molecules and/or trifluoromethanesulfonate ions act as bridges. DFT calculations could eliminate some structures due to the irrelevant structural parameters or the energetics of the proposed reactions.
(Less)
- author
- Łyczko, Krzysztof ; Więckowska, Agnieszka ; Bajnoczi, Éva G. ; Csupász, Tibor ; Purgel, Mihály ; Sigfridsson Clauss, Kajsa G.V. LU ; Tóth, Imre and Persson, Ingmar
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Decomposition rate, Dimethylsulfoxide, Mixed-valence thallium(III)-thallium(I) complex, N, N, N'N’-tetramethyl urea, Red-colored complex, Structure
- in
- Journal of Molecular Liquids
- volume
- 385
- article number
- 122233
- publisher
- Elsevier
- external identifiers
-
- scopus:85162926390
- ISSN
- 0167-7322
- DOI
- 10.1016/j.molliq.2023.122233
- language
- English
- LU publication?
- yes
- id
- 7efb1306-381c-40a0-8a27-eea34ceba575
- date added to LUP
- 2023-08-30 14:19:29
- date last changed
- 2023-08-30 14:19:29
@article{7efb1306-381c-40a0-8a27-eea34ceba575, abstract = {{<p>At the dissolution of solid anhydrous thallium(III) trifluoromethanesulfonate, Tl(CF<sub>3</sub>SO<sub>3</sub>)<sub>3</sub>, or thallium(III) trifluoroacetate, Tl(CF<sub>3</sub>COO)<sub>3</sub>, in dimethylsulfoxide (dmso) or N,N,N’,N’-tetramethylurea (tmu), intensely red-colored complexes are formed. This red thallium complex is stable for years in dmso, while it is reduced fairly rapidly to thallium(I) in tmu with a half-life time of an hour. At the dissolution of Tl(CF<sub>3</sub>SO<sub>3</sub>)<sub>3</sub> in N,N-dimethylpropyleneurea (dmpu) an immediate reduction to thallium(I) takes place. A stable colorless aqueous thallium(III) solution is obtained at the dissolution in acidic water. Stable dmso solutions and solid dmso solvates of thallium(III) perchlorate, nitrate and trifluormethanesulfonate can be prepared by adding dmso to concentrated acidic aqueous thallium(III) solutions. These experimental observations conclude that the pure solids Tl(CF<sub>3</sub>SO<sub>3</sub>)<sub>3</sub> and Tl(CF<sub>3</sub>COO)<sub>3</sub> play an essential role in the formation of the red-colored thallium complexes. <sup>205</sup>Tl NMR data show that the red thallium complex contains equal amounts of thallium(III) and thallium(I). The structure of the red thallium complex in dmso, as determined by EXAFS, has Tl–O bond distances of 2.216(3) and 2.80(2) Å, which are in very close agreement with the bond distances obtained in the pure dmso solvates of the thallium(III) and thallium(I) ions, respectively, and a Tl···Tl distance of 3.49(1) Å bridged by oxygen atoms. From the EXAFS data it is impossible to distinguish if dmso molecules and/or trifluoromethanesulfonate ions act as bridges. DFT calculations could eliminate some structures due to the irrelevant structural parameters or the energetics of the proposed reactions.</p>}}, author = {{Łyczko, Krzysztof and Więckowska, Agnieszka and Bajnoczi, Éva G. and Csupász, Tibor and Purgel, Mihály and Sigfridsson Clauss, Kajsa G.V. and Tóth, Imre and Persson, Ingmar}}, issn = {{0167-7322}}, keywords = {{Decomposition rate; Dimethylsulfoxide; Mixed-valence thallium(III)-thallium(I) complex; N, N, N'N’-tetramethyl urea; Red-colored complex; Structure}}, language = {{eng}}, publisher = {{Elsevier}}, series = {{Journal of Molecular Liquids}}, title = {{Striking stability of a mixed-valence thallium(III)-thallium(I) complex in some solvents}}, url = {{http://dx.doi.org/10.1016/j.molliq.2023.122233}}, doi = {{10.1016/j.molliq.2023.122233}}, volume = {{385}}, year = {{2023}}, }