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NMR signals of 133Cs have been measured in Csl, CsBr, CsCl, Cs2C03, Cs2S04, CsN03 and Cs2Cr04 powders relative to a 0.5 molal aqueous solution of CsCl. Combining these results with the shielding constant of the solution, which has been determined in former measurements, the nuclear magnetic shielding of 133Cs in the crystalline powders can be given in an atomic reference scale.The theoretical values of the shielding constant of 133Cs in CsCl, CsBr and Csl agree only in the order of magnitude with the experimental ones. For 133Cs in Cs2S04 a first-order quadrupole pattern has been observed.

109 Ag chemical shift measurements of 0.02 up to 3 molar solutions of AgNOa, AgCl, and AgBr in solvent mixtures of H2O (W) and ethylamine (ea) were performed. The extremely long relaxation times T\ and T2 were determined with new techniques.The Ag + -ion in solvent mixtures of W and ea shows a strongly selective solvation by ea. The 109 Ag chemical shift of the solvate complex [Ag ea2] + surrounded solely by W is 62 = (335 ± 2) ppm (referred to the Ag+-ion in W). A further solvation in addition to the inner solvation sphere was determined; this solvation is not or only weakly selective. There is a rapid chemical exchange; the lifetime of the inner solvation sphere is long compared with the Larmor period, whereas the solvation outside this sphere is changed in times shorter than the Larmor period.In contrast to the N03~-anion, the halide anions Cl~ and Br~ are partly coordinated to the [Ag ea2] + complex. The equilibrium constants for this coordination were determined as well as the chemical shifts of the [Ag ea2• Cl] and the [Ag ea2• Br] complexes. The bromine ion is coordinated for shorter times than the Larmor period, whereas the time of the coordination of the chlorine ion may be comparable to the Larmor period or shorter.