Alkali metal compounds, magnetic resonance

Ill] A. I. Popov The Use of Alkali Metal Nuclear Magnetic Resonance in the Study of Solvation and Complexation of Alkali Metal Ions, in J. F. Coetzee and C. D. Ritchie (eds.) Solute-Solvent Interactions, Dekker, New York, London, 1976, Vol. 2, p. 271ff. A. I. Popov Alkali Metal, Mag-nesium-25, and Silver-109 NMR Studies of Complex Compounds in Nonaqueous Solvents, in G. Mamantov (ed.) Characterization of Solutes in Non-Aqueous Solvents, Plenum Publ. Corp., New York, 1978. [111a] P. Laszlo Kernresonanzspektroskopie mit Natrium-23, Angew. Chem. 90, 271 (1978) Angew. Chem. Int. Ed. Engl. 17, 254 (1978). [112] N. A. Matwiyoff, P. E. Darley, and W. 

The pulse Fourier transform approach to magnetic resonance spectroscopy has been extensively developed and successfully applied to systems of one-half spin and their mutual interactions. But resonance spectroscopy of spin systems with the higher half- and integer spin quantum numbers is commonplace, for example, in the case of alkali metal nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) of transition metal compounds involving multi-quantum transitions. Similarly, magnetic resonance at zero field entails the observation of multi-quantum transitions. 

Magnetic Resonance Studies of Polytertiary Amine Chelated Alkali Metal Compounds... 

The high reactivity of chelated lithium alkyl compounds severely limits structural study of pure compounds, particularly in aromatic solvents. Most of our more recent work on chelated lithium alkyl systems used H and 7Li NMR to observe various metalation reactions like the self-metalation or aging reaction of TMED LiBu in heptane (I, 2). Much of our current insight into the structural features of chelated alkali metal systems comes from careful quantitative study of systems with relatively stable anions like resonance stabilized carbanions (5) and the systems described in this paper. We discuss magnetic resonance experiments on two systems (a) chelated lithium halides Chel LiX, examples of the recently discovered inorganic salt chelates (6), and (b)... 

The spectral maxima at 320, 390, and 590 nm were found to correspond to absorptions by the ions S , S , and S7, respectively. Direct observations (resonance Raman, i.r., and e.s.r. spectra) and indirect measurements (visible— u.v. spectra, conductivity, and magnetic susceptibility) strongly suggest that the intensely blue species formed by alkali-metal polysulphides or elemental sulphur in hexamethylphosphoramide can be attributed to the Sj radical anion. Cryoscopic, conductance, and magnetic measurements euid i.r. and u.v. spectral data have been used to study the cations formed in solutions of sulphur in disulphuric acid. The blue coloration was shown to be due to the formation of the Si" " ion and the colourless solutions were found to contain the S ion. The solid compounds S4S30ioand 8383010, formed by the action of SO3 on elemental sulphur in 8O2 media at low temperatures, have been isolated and characterized. 

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