Nuclear Quadrupole Spectra in Very Asymmetric Field Gradients

Pure nuclear quadrupole resonance spectra in asymmetric field gradients are discussed. Contrary to the usual approach, the fully asymmetric case (η=1) is taken as a starting point. It is shown that in this case the Hamiltonian has an important symmetry property, which gives information on the energy‐level spectrum and relations between the eigenfunctions. Closed solutions in terms of quadratic equations can be obtained for spins up to $\frac{9}{2}$ . A perturbation expansion around η=1, which seems to converge very well, is also described.