Nuclear quadrupole resonance in crystals with reorientational motion between unequal potential wells

Authors

  • Игорь Александрович Кюнцель (Igor A. Kyuntsel) Perm State University

DOI:

https://doi.org/10.17072/1994-3598-2018-2-35-44

Keywords:

ядерный квадрупольный резонанс, неравноямные реориентации, неэквивалентные квадрупольные ядра

Abstract

Effect of the reorientation motion of molecules and separate molecular fragments occurring between the positions with unequal potential energy, on the NQR frequency and the time T1 of the spin-lattice relaxation of chemically and crystallographically nonequivalent resonant nuclei directly participating in the reorientational motion are considered. In the temperature dependences of these parameters, the following characteristic features are observed: the reorientational fade out temperatures of the resonant signals for nonequivalent nuclei can vary significantly; exponential (reorientational) parts of dependencies logT1 vs 1/T of these nuclei are parallel; the spin-lattice relaxation times caused by the reorientation mechanism become substantially longer. We discuss a qualitative relation of these features with the potential energy difference between the orientation positions on the one hand and with the angle between the rotation axis and the direction of the electric field gradient for nonequivalent quadrupole nuclei on the other hand.

References

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Published

2018-07-13

How to Cite

Кюнцель (Igor A. Kyuntsel) И. А. (2018). Nuclear quadrupole resonance in crystals with reorientational motion between unequal potential wells. Bulletin of Perm University. Physics, (2(40). https://doi.org/10.17072/1994-3598-2018-2-35-44

Issue

Section

Regular articles