Magnetic Nuclear Resonance Applied to the Study of Amorphous Materials Resonance Magnetique Nucleaire Appliquee a l'Etude des Corps Amorphes.

摘要

The application of NMR to amorphous materials at very low temperatures is reported. Theoretical foundations of the method are detailed with regard to nuclear spin definition and properties, free spin behavior in the magnetic field, quadrupole moment, nuclear relaxation, and spin-lattice relaxation. The experimental technique is reviewed with regard to the pulsed Clarke spectrometer and the cryostat. Measurements are possible between 1.2 and 4.2 degrees Kelvin. Parameters investigated were specific heat, thermal conductivity, and spin-lattice relaxation. Results are discussed with regard to the degree of crystallinity and compared to results of other authors. Experiments were performed on selenium and a boron oxide, the latter in both forms - amorphous and crystalline.