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 Å^-1, where they amount to approximately 5% of the form factor at that value of K.