Inhomogeneous Dipolar Broadening and Hyperfine Shifts of Protons Resonance Lines in Solution with Paramagnetic Impurities
We determine the frequency shift and the inhomogeneous broadening of the NMR lines of nuclei I in solution and in presence of paramagnetic impurities with electronic spin S, due to dipolar interactions. This effect which depends on the shape of the liquid sample is studied for various geometries. When scalar hyperfine interactions are present there is an additional frequency shift which is calculated in function of the coupling constant depending on the interspin I-S distance. These effects are analyzed on proton NMR spectra of tetramethylammonium ions in heavy water solution in presence of paramagnetic Mn2+ impurities.