Resonance Methods for Liquids and Solids

We wiU now discuss resonance techniques that are useful for studying liquid and solid samples. In these methods the differences hr population between magnetically separated sublevels, due to the thermal Boltzmann distribution, are utilized. Magnetic field splittings are always small in comparison to fcT, which is about 1/40 eV at room temperature. Thus population differences will always be small, and the number of atoms required is much larger than for 

Nuclear Magnetic Resonance. The NMR technique utihzes the macro-scopic magnetic moment resulting from the nuclei in the sample. In an external magnetic field B the nuclear spin I can have 21 - -1 different orientations. The energy of a magnetic sublevel is given by 

The technique we have discussed so far is the continuous-wave (stationary) method. For a constant magnetic field, the frequency of the oscillator, which generates a field with an amplitude of about 10 T, is slowly swept and 

Modern NMR spectroscopy frequently uses pulsed RF radiation and the observation is performed instead in the time domain. Pulsed NMR can be utilized in different ways. If a short pulse of high field strength Bi 10-3 

A diagnostic appheation of NMR in the medical field has been made possible through the development of the NMR imaging (tomographic) technique 

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