Proton and deuterium nuclear magnetic resonance study of paramagnetic solution in cerium (iii) nitrate

The dependence of the spin-lattice relaxation rate of H and D nuclei immmersed in a 2.1 Tesla magnetic field, on the concentration of Ce3+ paramagnetic ions (between 0 and 3M, M=moles of solute per 1000 g of solvent) is presented for temperatures between 253 and 373 K. Its dependence on frequency was also investigated, and was found to be linear. A small difference was observed in the behaviour of the H and D relaxation rates in the range of concentration between 1.5 and 1.7 M of Ce3+ ions, probably due to a difference in the symmetry of the complex. A similar phenomenon was detected at 283 K. The hyperfine interaction anisotropy (and, in the case of D the electric quadrupolar) relaxation mechanism is proposed to explain the data