Relaxation of Chloride, Bromide and Iodide Ions

Abstract

As in the case of covalent compounds, chlorine, bromine and iodine relaxation is for the halide ions (except for certain paramagnetic systems) dominated by time-modulated interactions between the nuclear electric quadrupole moments and inhomogeneous electric fields. Although the general relaxation mechanism is the same, the theoretical treatment and the applications are distinctly different in the two cases. This can be referred to the different origins of the field gradients causing relaxation. For a covalent environment the electric field gradients are of intramolecular origin and the value of the quadrupole coupling constant can often be determined separately by different methods. Therefore, as described in Chapter 2, quadrupole relaxation studies of covalent compounds are almost exclusively concerned with the determination of the correlation time of molecular reorientation.