Electric quadrupole interactions measured by nuclear orientation and NMR on oriented nuclei

A review is given of the situations in which low temperature nuclear orientation and NMR of oriented nuclei have been applied in recent years to the measurement of electric quadrupole interactions in metals and in dielectric crystals. The review is concerned with the variety of methods by which quadrupole interactions have been measured. Illustrative examples are given for each technique, but no attempt is made to give a full bibliography of work. As regards nuclear orientation, pure quadrupole algnment is discussed (although in non-cubic metals rather than in dielectric crystals), followed by outlines of work on mixed magnetic dipole and electric quadrupole hfi when these interactions are (a) co-axial and (b) mutually perpendicular. The sensitivity of nuclear orientation to small quadrupole interactions is shown to be improved in the second case.For NMR on oriented nuclei the review centres upon the small quadrupole effects detected in dilute ferromagnetic alloys both by direct observation of resonance line structure and by interpretation of signals following adiabatic fast passage.Republished from the XVIIth Winter School on Physics (Hyperfine Interactions) held from February 19-March 3, 1979 in Bielsko Biala (Poland), with the kind permission of the Editors.