Intermultiplet transitions

R. Osborn, S.W. Lovesey, A.D. Taylor and E. Balcar, Intermultiplet transitions using neutron spectroscopy 1... 

We have designated as Coulomb transitions those intermultiplet transitions in which ALt O, i.e., transitions between levels derived from different Russell-... 

Fig. 7. Neutron inelastic structure factors for intermultiplet transitions in thulium. The lines represent the calculated intensites, taking intermediate coupling into account, of the (smooth line),...

In spite of this established potential, neutron scattering has so far made only a limited contribution in the field of intermultiplet spectroscopy. This is for two reasons. Firstly, intermultiplet transitions have relatively low cross-sections. Only the /->/ l transitions (AL = A5 = 0) are magnetic dipole allowed, i.e., their cross-sections are non-zero at zero momentum transfer k, and even these are an order of magnitude weaker than the scattering within the ground state multiplet... 

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