Comparison of Hartree-Fock and Hartree-Fock-Slater approximations for calculation of radiation damage dynamics of light and heavy atoms in the field of an x-ray free-electron laser

Abstract

Simulations of radiation damage in single-molecule imaging using an x-ray free-electron laser use atomic rates calculated in the lowest order. We investigate the difference in ion yield predictions using Hartree–Fock and Hartree–Fock–Slater approximations for light and heavy elements of biological significance. The results show that for the biologically abundant elements of the second and third rows of the periodic table both approximations agree to within about 6%. For the heavier elements beyond the fourth row the discrepancy rises to 11% for the range of pulse parameters covered in this work. The presented analysis can be used for error estimation in a wide range of ab initio simulations ..