Molecular Form Factors and Photon Coherent Scattering Cross Sections of Water

Abstract

Tabulations are presented of molecular form factors F(x), for values of x=sin(θ/2)/λ from 0 to 1.25 Å−1, for liquid water at eight temperatures between 4 °C and 200 °C and for the free water molecule. For liquid water, x=0 to 1.25 Å−1, the tabulated values are interpolated from experimental values of Narten and Levy (1971). For the free water molecule, x=0 to 1.25 Å−1, the tabulated values are interpolated from calculated values of Blum (1971). For x=1.25 to 109 Å−1, the independent atomic scattering hypothesis is assumed and the water molecular form factor F(x) is calculated from the hydrogen and oxygen atomic form factors given by Hubbell and Overbo (1979). Tables of coherent scattering cross sections, obtained by numerical integration of the Thomson formula, weighted by F2(x), are presented for liquid water at eight temperatures between 4 °C and 200 °C and for the free water molecule, for photon energies 5 keV to 1 MeV.