We show that, in the fast collision approximation, the scattering oper
ator for resonant x-ray scattering can be expressed in terms of simple
spin-orbital moment operators M(k) (1, s) of the valence shell involv
ed in the resonance. This theory is applicable to the analysis of a br
oad range of resonant x-ray elastic and inelastic scattering and absor
ption experiments involving rare earth, actinide, and transition eleme
nts.