The effect of configuration interaction on atomic scattering factors for transition metals

Spin-only magnetic form factors and X-ray form factors for Mn, Mn+, Co, Co2+, Ni and Ni2+ are calculated using configuration interaction wavefunctions. The magnetic form factors for Co2+ are used in the analysis of polarized neutron diffraction data for Cs3CoCl5, to give spin populations. The inclusion of correlation functions in the wavefunction leads to changes in Hartree-Fock form factors of transition metal atoms, which maximize at K/4π ~ 0.4 A-1, where they amount to approximately 5% of the form factor at that value of K.