Relativistic Calculation of Anomalous Scattering Factors for X Rays

Abstract

Anomalous scattering factors $\mathrm{\Delta f\prime }$ and $\mathrm{\Delta f″}$ have been calculated relativistically for Cr, Fe, Cu, Mo, and Ag $\mathrm{K\alpha }$ radiations for the atoms Li through Cf. An interpolation scheme for other wavelengths is included in a separate report. Relativistic calculations of the photoelectric cross section have been made and the integral for the principal contribution to $\mathrm{\Delta f\prime }$ has been evaluated numerically without approximation to the form of the cross section‐vs‐energy curve, as has been done in previous calculations. Many of the results are significantly different from previous calculations. Where experimental values exist, agreement for $\mathrm{\Delta f″}$ is improved. For the rare gases, except for xenon, agreement between $\mathrm{\Delta f\prime }$ and experiment is improved. Because of the more rigorous evaluation of $\mathrm{\Delta f\prime }$ from cross‐section information, it is presumed that the present $\mathrm{\Delta f\prime }$ values are more accurate than previous calculated values. Calculated mass absorption coefficients for the elements are included as incidental information.