13453-40-2Relevant articles and documents
Solvent Dependence of Kinetics and Equilibria of Thallium(I) Cryptates in relation to the Free Energies of Solvation of Thallium(I)
Cox, Brian G.,Stroka, Jadwiga,Schneider, Irmgard,Schneider, Hermann
, (1989)
Stability constant and dissociation rate constants of thallium(I) cryptates have been measured in several solvents at 25 deg C.The Tl+ cryptates are more stable and less sensitive to ligand cavity size than the corresponding complexes of the al
205Tl, 14N, and 1H NMR Studies of Salt Solutions in Liquid Methylamine
Metz, K. R.,Hinton, J. F.,Goforth, T. L.
, p. 2097 - 2102 (1985)
205Tl, 14N, and 1H NMR techniques were used to investigate thallium(I) salt solutions in liquid methylamine from 1 mM to 7.2 M.Essentially complete association was observed between Tl+ and NO-3 or HCO-2 at 1 mM.Thermodynamic parameters for the ion association of Tl+ and ClO-4 were found to be ΔHA = +10.3 +/- 4 kcal mol-1 and ΔSA = +50 +/- 15 eu.Due to its lower dielectric constant, more extensive ion association occurs in liquid methylamine than in liquid ammonia.Ion pairs in liquid methylamine appear to be of solvent-shared or solvent-separeted type, as opposed to contact ion pairs previously found to exist in liquid ammonia.Relative anion and solvent donicities, as determined from 205Tl chemical shifts, were strongly temperature dependent.At high concentrations, no evidence for a structural rearangement of the solvated TlNO3 species was found.However, the anomalous behavior of the 205Tl chemical shift observed at TlNO3 concentrations below 0.5 M may results from such rearrangements.Two methylamine molecules were determined to be the minimum number necessary to saturate the associated ionic species at very high concentrations.
Solvent isotope effects on the complexation and exchange kinetics of Tl(I), K+ and Na+ with 18-crown-6 by competitive NMR spectroscopy: Competition between homo- and heterobimolecular cations exchange
Alizadeh, Naader,Haddadi, Hedayat
, p. 1267 - 1273 (2011)
The thermodynamic properties of complexation and exchange kinetics of thallium by 18-crown-6 have been studied by thallium NMR spectroscopy. Effects of solvent isotope, counterion (ClO4- and NO 3-) and presence of competitive cations, such as Na + and K+, on the exchange characteristics of the system have been considered. The obvious relationships between the effects of D 2O-H2O solvent isotope on the thermodynamic properties and activation parameters of complexation have been investigated. In the absence of competitor cations, the mechanism of thallium exchange is unimolecular decomplexation and in the presence of competitor cations, homobimolecular cation exchange is the predominant mechanism at low concentrations of the ligand. At higher concentrations of the ligand, the measured rate constants show that the complexation/decomplexation process obeys a heterobimolecular cation interchange mechanism. The rate constants ratios (kD2O/kH2O 1) for unimolecular mechanisms also show an inverse solvent isotope effect.
Novel bis(diethylenetriamine)thallium(III) complex. Synthesis and characterization in pyridine solution and in solid
Kritikos, Mikael,Ma, Guibin,Bodor, Andrea,Glaser, Julius
, p. 224 - 231 (2002)
A new complex of thallium(III) with the nitrogen donor ligand diethylenetriamine (dien) has been prepared and characterized by multinuclear NMR (1H, 13C, 205Tl), infrared and Raman spectroscopy, and X-ray diffraction. In solution, the symmetric s-facial isomer of [Tl(dien)2]3+ is formed. This is a fluxional molecule even at low temperature (235 K); therefore, the different rotamers cannot be observed separately. A complete characterization of the complex is given from its non-trivial NMR spectra. The crystal structure of [Tl(dien)2](ClO4)3·H2O shows u-facial geometry, where the coordination environment around thallium can be described as a distorted trigonal prism.
Viscosity measurements of some tetrabutylammonium, copper(I), silver(I) and thallium(I) salts in acetonitrile-pyridine mixtures at 15, 25 and 35 deg C
Gill, Dip Singh,Singh, Balbir
, p. 4417 - 4426 (1988)
Viscosities and molar conductances of Bu4NBPh4, Bu4NClO4, CuClO4*4AN, AgClO4 and TlClO4 have been measured in the concentration ranges (30-425)E-4 mol dm-3 and (1-35)E-4 mol dm-3, respectively in acetonitrile-pyridine (AN-Py) mixtures containing 0, 10, 20, 40, 60, 80, 90 and 100 molpercent AN at 15, 25 and 35 deg C.The viscosity data have been analysed using the Jones-Dole equation in the form: η/η deg = 1 + AC1/2 + BC for unassociated electrolytes and in the form: η/η deg = 1 + A(Cα)1/2 + BCα + B'(1-α)C for the associated electrolytes.The A-coefficients of the Jones-Dole equation are positive and in reasonably good agreement with the limiting theoretical values (Aη) calculated at all the three temperatures using Falkenhagen-Vernon equation.The B-coefficients of the electrolytes are also positive and large in all cases and show a significant decrease with increase in temperature.The ionic B+ and B- coefficients have been evaluated from the B-coefficients of the electrolytes using a method reported by Gill and Sharma.The derived viscosity results show preferential solvation of Cu+, Ag+ and Tl+ by Py in AN-Py mixtures at all the temperatures studied.
Electrochemical Generation of Soluble and Reactive Cadmium, Lead, and Thallium Cations in Noncoordinating Solvents: Relative Strengths of Perchlorate, Tetrafluoroborate, and Hexafluorophosphate Ligation in Dichloromethane and Benzene
Bond, Alan M.,Ellis, S. Richard,Hollenkamp, Anthony F.
, p. 5293 - 5297 (1988)
Electrochemical oxidation of metal amalgam electrodes in noncoordinating solvents generates soluble forms of highly active metal ions at the electrode surface that can form very strong complexes with the tetrafluoroborate and perchlorate anions.Oxidation at Cd, Pb, and Tl dropping mercury amalgam electrodes in a solution containing dichloromethane and either tetrabutylammonium hexafluorophosphate, , tetrabutylammonium tetrafluoroborate, , or tetrabutylammonium perchlorate, , occurs reversibly, thereby allowing thermodynamic data to be obtained on the nature of the complex formed.The - ligation is considerably weaker than that of - or -.Data obtained in dichloromethane with hexafluorophosphate, as a reference electrolyte allowed the following complexes with their equilibrium constants to be identified: 2-, log β4=9.1; -, log β3=7.3; -, log β3=8.3; Pb(BF4)2, log β2=7.5; Tl(ClO4), log β1=3.3; Tl(BF4), log β1=2.9.The equilibrium constants for these complexes are larger then those obtained in aqueous media for many classical ligands.In benzene, which is of lower dielectric constant and is less polar than dichoromethane, the half-wave potential for the oxidation of the cadmium amalgam electrode is approximately 700 mV more negative with pechlorate than with hexafluorophosphate as the electrolyte anion.In contrast, the difference is only 200 mV in dichloromethane.This unprecendented difference may be attributed to the weaker coordination of benzene and the consequent amplification of the differences in strength of perchlorate and hexafluorophosphate ligation.Consequently, a method of preparing highly activated and previously unknown forms of soluble metal ions is available in solvents such as chlorinated and aromatic hydrocarbons. This feature is further illustrated by the large negative shift in half-wave potential for the metal oxidations observed after the coordinating solvent dimethyl sulfoxide is added to dichloromethane (0.2 M ) solutions.Controlled-potential electrolysis experiments at a mercury amalgam pool in dichloromethane lead to the formation of the expected nonsolvated insoluble salts, demonstrating that the kinetics of precipitation are slower then the polarographic time scale.Concepts developed on this work provide prospects for new forms of mechanistic, thermodynamic and synthetic metal ion chemistry.
Dynamic NMR study of the kinetics of complexation of Tl+ ion with Calix[4]crown-6
Haddadi, Hedayat,Alizadeh, Naader,Shamsipur, Mojtaba,Asfari, Zouhair
, p. 7462 - 7469 (2010)
The complexation and exchange kinetics and mechanism for the dissociation and conformational change of thallium ion complex of calix[4]crown-6 were studied in CD3CN/CDCl3 (4:1 v/v) solution by dynamic 1H NMR. The results show the formation of a 1:1 complex with cone conformation. From variable temperature dynamic NMR analysis in the range 223-293 K, two coalescence temperatures at 228 and 243 K were ascertained. The activation parameters for the dissociation process, Ea (kJ/mol), δS? (J/mol.K), and δH? (kJ/mol) are 11.0, -133.2, and 10.1 for the bimolecular regime and 21.5, -112.8, and 20.6 for the unimolecular regime, respectively. In addition, the dynamic 1H NMR spectroscopy shows that the exchange of Tl+ between the two crown sides of the complexed ligand proceeds through an intramolecular tunneling. An Arrhenius convex curve was observed for intramolecular exchange. This phenomenon is explained in terms of two conformer state formations differentiated by hydrogen bond association.
Small Platinum-Thallium Clusters Stabilized by Ethylenediamine, [(NC)5Pt-Tl(en)n-1] (n = 1-3) - Characterization in Solution and in the Solid State
Ma, Guibin,Kritikos, Mikael,Glaser, Julius
, p. 1311 - 1320 (2007/10/03)
Three neutral binuclear platinum-thallium compounds containing a direct and naked (unsupported by ligands) metal-metal bond have been prepared in dimethyl sulfoxide (DMSO). The compounds have the formula [(NC)5Pt-Tl(en)n-1] (n = 1-3, for compounds 1, 2 and 3, respectively) and were found to exist in solution by means of multinuclear NMR (195Pt, 205Tl, 13C and 1H) and Raman spectroscopy. The compounds exhibit very large single bond 195Pt-205Tl spin-spin coupling constants of 48-66 kHz. In addition, the solid state analogues of 1 and 3, [(NC)5Pt-Tl(DMSO)4](DMSO) and [(NC)5Pt-Tl(en)2](DMSO)2, were synthesized and their structures determined by single crystal X-ray diffraction. The metal-metal bond lengths of Pt-Tl are 2.6131(4) Angstroem and 2.6348(5) Angstroem in compounds 1 and 3, respectively. Crystal data for compound 1: monoclinic, space group Cc(No. 9), Z = 4, a = 17.2367(14, b = 9.5560(11), c = 17.7941(15) Angstroem, β = 100.551(10) deg, V = 2881.4(5) Angstroem3, T = 110(1) K; and for compound 3: monoclinic, space group P21 (No. 4), Z = 2, a = 9.3167(14), b = 12.3007 (13), c = 11.4586(16) Angstroem, β = 112.318(16) deg, V = 1214.8(3) Angstroem3, T = 110(1) K.
