Magnetic Resonance Electrical Impedance

Instead of tuning co f one may also vary the dc magnetic or electric field at a fixed value of co f thus tuning the Zeeman or Stark splittings into resonance with the fixed radio frequency (Sect. 1.7). This has the experimental advantage that the RF coil can be better impedance-matched to the RF generator. 

Quadrupolar nuclei constitute most of the magnetic nuclei within the Periodic Table of the elements. However, the lack of suitable instrumentation as well as the misconception of the deleterious nature of these nuclei have impeded a more widespread utilization of their resonances. Quadrupolar relaxation resulting from the interaction of the nuclear quadrupolar moment with finite electric field gradients is the principal source of nuclear relaxation in nearly all compounds. However, albeit generally eonsidered a nuisance, the phenomenon may as well be exploited to the experimenter s advantage. In contrast to spin-j nuclei whose relaxation behaviour is principally dictated by the dynamics of the molecules in solution, structural and electronic effects play the key role in the relaxation process of quadrupolar nuclei. 

Garcia-Arribas Alfredo, Gutierrez Jon, Kurlyandskaya V. Galina, et al. Sensor applications of soft magnetic materials based on magneto-impedance, magneto-elastic resonance and magneto-electricity. Sensors. 14 no. 5 (2014) 7602-7624. 

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