Theory of neutron scattering from localised electronic excitations

The matrix elements which determine the magnetic inelastic neutron cross-section for scattering by localised electronic states are calculated for the transition lmsmsub(s) → l'm'sm'sub(s). Use of the formulae is illustrated in a calculation of the neutron cross-section for scattering from thallium-activated potassium chloride (when the thallium ion changes its configuration from 6s2 to 6s6p) and the associated atomic structure factors are estimated on the basis of free-atom wavefunctions. (author)