¹⁰⁹Ag Nuclear Magnetic Resonance Studies of Organic and Inorganic Silver Complexes

Abstract

The NMR lines of 109Ag have been investigated in solutions of several silver salts in acetonitrile, propionitrile, pyridine, and ethylenediamine, and also in aqueous solutions of Na2S2O3 and ethyl-amine. In these solvents the Ag+ -ions form one or several complexes. In any case a single NMR line was to be detected, i. e. a rapid chemical exchange between different complexes in a sample may be assumed. The concentration dependence of the chemical shifts was determined with high accuracy for these solutions. From these results the chemical shift data of some defined complexes were derived. The chemical shifts of mixtures of AgCl and AgBr and also of AgCl and Agl dissolved in 70% aqueous solution of ethylamine are linear functions of the anions mole fraction. In two samples of AgNO3 dissolved in organic solvents, the ratio υ(109Ag)/υ(107Ag) = 1.149 640 (1) was measured in good agreement with the value from silver salts in aqueous solutions; i. e. no primary isotopic effect was to be detected within these limits of error (0.9 ppm).

[(CF3)4Au2(C5H5N)2] – a new alkyl gold(ii) derivative with a very short Au–Au bond

“…A similar reaction procedure was reported by Fernandez and co workers on the syntheses of the bimetallic complex [Ag(Py pointed out that the shift strongly depended on the Ag + concentration, whereby the formation of a linearly coordinated silver complex [Ag(Py) 2 ] + exhibited to be thermodynamically preferred. 4 Although trifluoromethyl derivatives are known for both Ag(I) and Au(I), no evidence was found so far for an chemical exchange between [(CF 3 )Ag] 5 and [(CF 3 )Au] 1 derivatives, which would cause at least a significant line broadening in the 19 F NMR spectra recorded at ambient temperature. The Ag-Au derivative [Ag(Py) 2 ][Au(CF 3 ) 2 ] can be seen exclusively as a silver(I) aurate(I).…”

Mobility of Silver Ions in Silver Ion Conductor Ag7NbS6 Studied by Ag and Nb NMR

“…At room temperature, motional narrowing of the 109 Ag line shape in all the measured samples has been completed, and the chemical shifts can be obtained precisely. Table compares the chemical shifts of the Ag 7 - 9 MX 6 type compounds with those of other silver compounds. − The shifts are much larger than those of other silver compounds, including silver ionic conductors. Figure shows the temperature dependence of the chemical shift of 109 Ag of Ag 7 NbS 6 , and the temperature coefficient is −0.5 to −0.3 ppm/K.…”

“…Table 1 compares the chemical shifts of the Ag 7-9 MX 6 type compounds with those of other silver compounds. [10][11][12][13][14] The shifts are much larger than those of other silver compounds, including silver ionic conductors. Figure 1 shows the temperature dependence of the chemical shift of 109 Ag of Ag 7 NbS 6 , and the temperature coefficient is -0.5 to -0.3 ppm/K.…”

109Ag NMR-Studies of the Selective Solvation of the Ag+ -Ion in Water-Ethylamine-Mixtures and of the Coordination of Halide-Anions to the Silver-Ethylamine Solvate Complexes

“…In contrast to the N03~-anion, which yields a nearly linear dependence of the 109 Ag chemical shift on the AgN03 concentration, it was pointed out in a recent paper [4] that the 109 Ag chemical shifts of solutions of the silver halides AgF, AgCl, AgBr, and Agl are spread over a range from 430 ppm to 790 ppm (related to the resonance of the Ag + -ion in H.,0 at infinite dilution), whereas the shift of each of the halides is only slightly depending on the Agconcentration in the range >0.5 molal. Particularly there is no convergence of the four chemical shifts to a common value for Ag-concentration 0.…”

“…Unfortunately the chemical shifts of these ligand protons are relatively small (some ppm), and thus information taken from such experiments is limited. In the last few years, however, special steady-state pulse techniques have become available and enabled systematic NMR investigations of the nuclei 107 Ag and 109 Ag [3,4]. The silver chemical shifts are found to be in the range of some hundreds of ppm and suggest investigations on the central atom of the solvate complex.…”