Theoretical Calculation of Relative Intensities in ESCA

Calculations of the photoionization cross-sections of atomic and molecular levels for the A1 K α and Mg K α lines depending on the wave function of the final and the initial states are analysed. The ns, np and nd photoionization cross-sections of atomic shells for Z ⩽ 36 and the HF, NH 3 , H 2 O, CH 4 , CH 3 F, CH 2 F 2 , CHF 3 , CF 4 , N 2 , CO and C 2 H 4 molecular levels for the Y M ζ line and the photoionization cross-sections of atoms for Z ⩽ 36 and the CH 4 , N 2 and H 2 O molecular levels for the Zr M ζ line are calculated. The theoretical cross-sections of atoms for Z ⩽ 10 for the F K α line are presented too. Photoionization cross-section calculations using Hartree-Fock-Slater potential are in better agreement with the experiment than those using orthogonalized plane waves for photo-electron wave functions.