Tabulations are presented of the atomic form factor, F(x,Z), and the incoherent scattering function, S(x,Z), for values of x (=sin (IJ/2)/X,) from 0.005 A-I to 10 9 A-1, for all elements Z=l to 100. These tables are constructed from available state-of-the-art theoretical data, including the Pirenne formulas for Z = 1, configuration-interaction results by Brown using Brown-Fontana and Weiss correlated wavefunctions for Z=2 to 6, non-relativistic Hartree-Fock results by Cromer for Z=7 to 100, and a relativistic K-shell analytic expression for F(x,Z) by Bethe and Levinger for x> 10 A-I for all elements Z =2 to 100. These tabulated values are graphically compared with available photon scattering angular distribution measurements. Tables of coherent (Rayleigh) and incoherent (Compton) total scattering cross sections, obtained by numerical integration over combinations of F2(X.z) with the Thomson formula and S (x,Z) with the Klein-Nishina formula, respectively, are presented for all elements Z= I to 100, for photon energies 100 eV (1..=124 A)lto 100 MeV (0.000124 A). The incoherent scattering cross sections also include the radiative and double-Compton corrections as given by Mork. Similar tables are presented for the special cases of terminally-bonded hydrogen and for the H2 molecule, interpolated and extrapolated from values calculated by Stewart et al. and by Bentley and Stewart using Kolos-Roothaan wavefunctions.

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The usual expressions for the Compton effect are based on the assumptions that the scattering electron is free and stationary. These assumptions are reasonable when the photon energy is large compared to the electron binding energy; however, in many situations this is not the case, and the binding energy and momentum of the electron alter Compton scattering by causing (1) line broadening, (2) a discrete spectrum, (3) a line-shift defect, (4) a decrease in incoherent scattering at low angles, (5) an increase in coherent scattering at low angles, and (6) a change in recoil electron distribution. These effects are described, and differential and average cross sections for carbon are calculated on the Thomas-Fermi model to illustrate them quantitatively.