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As there are different types of pictures on the molecular dynamical states in solid methane. especially concerning the λ-transition at 2042°K. we have investigated how the new method of nuclear magnetic resonance throw light on such problem. Both one parameter theory and the method of perturbation were applied to the analysis of the proton resonance data due to Thomas, Alpert and Torsey.<BR>Characteristic time τc for the molecular reorientation was estimated from the spin-lattice relaxation deta, and it was found that above 20°K molecules are reorientating in the classical sense, jumping over hindrances due to neighbouring molecules. At about 65°K a marked alternation is present in the dominant mechanism of the above reorientation, which is considered either correlated or independent molecular rotation.While, below 20°K the greater part of molecular are in the ground state of rotational oscillation and occasionally (about 10 times per second) tunnel or flip to neighbouring equivalent orientations. It was proposed that we should discriminate two pictures of local magnetic field in relation to the observing frequency and was made sure by reproducing absorption line width, Perturbational calculations taking account of the above sctuation gave the whole shape of absorption line, which was in good agreement with the experimental one observed by Alpert in the lowest temperature region.
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