Magnetic susceptibility inhomogeneities

The convenient NMR observables depend on the characteristics of the system studied, but generally the protons of the liquid are readily detected. The apparent NMR linewidths are often determined by the magnetic susceptibility inhomogeneities in the sample and do not directly reflect the dynamics of the liquid. This report will focus largely on theoretical approaches to understand the spin-lattice relaxation rate constants for both classes of microporous materials. The magnetic held dependence of the spin-lattice relaxation rate constant generally provides a useful dynamical characterization of the liquid and often a structural characterization of the confining media. 

Two-component systems have received some attention. - Poly(vinyl-idene fluoride>-poly(methyl or ethyl methacrylate)s blends have been mentioned in the previous section. A study of compatibility in blends of poly(vinyl chloride) and ethylene-vinyl acetate copolymer (EVA) has been reported. Spin-lattice relaxation time measurements were bi-exponential corresponding to rigid [poly(vinyl chloride)] and mobile (EVA) phases. A precipitated mixture showed intermingling of EVA in the poly(vinyl chloride) phase, but phase separation occurred on heating. Cashell et a/. have contributed a short note on the effects of magnetic susceptibility inhomogeneities of lincwidths in carbon black-filled... 

The deflection of clusters by an inhomogeneous magnetic field provides an indication of their magnetic susceptibility. Similar deflection in a static electric field has also been performed for alkali beams and is planned for the transition metals in order to obtain polarizabilities as a function of cluster size. 

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