Solid in the constant magnetic field and high frequency alternating electromagnetic field *** with the action, at a certain frequency near the *** vibration absorption phenomenon of high frequency electromagnetic field. In the constant external magnetic field under the action of solid magnetization, solid in the metamagnetic moment are to be around the external magnetic field into action. Due to the presence of damping, this in-motion is quickly attenuated. But if a high-frequency electromagnetic field perpendicular to the direction of the external magnetic field, when its frequency and the frequency of the same into the action, it will be absorbed from the alternating electromagnetic field in order to maintain its into the action of the solid on the incident high-frequency electromagnetic field energy in the frequency of the above to produce a * * * vibration absorption peak. If the magnetic *** vibration of the magnetic moment is a paramagnetic body in the atomic (or ion) magnetic moment, it is called paramagnetic *** vibration; if the magnetic moment is the atomic nucleus of the spin magnetic moment, it is called nuclear magnetic *** vibration. If the magnetic moment is the spin magnetic moment of an electron in a ferromagnet, it is called a ferromagnetic **** vibration. The nuclear magnetic moment is about three orders of magnitude smaller than the electronic magnetic moment, so the frequency and sensitivity of the nuclear magnetic **** vibration is much lower than the paramagnetic **** vibration; similarly, the magnetic **** vibration sensitivity of weakly magnetic substances is lower than that of strongly magnetic substances. From a quantum mechanical point of view, the magnetic moment of the electron and the nucleus under the action of the external magnetic field is spatially quantized, and accordingly has a discrete energy level. When the applied high-frequency electromagnetic field energy hv is equal to the spacing between the energy levels, the electron or atomic nucleus from the high-frequency electromagnetic field to absorb energy, so that it from the low energy level jump to the high energy level, so that the formation of absorption peaks in the *** vibration frequency.
The use of paramagnetic *** vibration can study the molecular structure and the electronic structure of defects in crystals and so on. Nuclear magnetic **** vibration spectrum is not only related to the chemical elements of the material, but also affected by the chemical environment around the atom, so nuclear magnetic **** vibration has become an important means to study the structure of solids, chemical bonding and phase transition processes. Nuclear magnetic **** vibration imaging technology with ultrasound and X-ray imaging technology has been commonly used in medical examinations. Ferromagnetic *** vibration is an important method to study dynamic processes in ferromagnets and to measure magnetic coefficients.
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