A consistent spherical potential function for para-hydrogen

Several potential functions have recently been proposed to fit physical properties of hydrogen. We have calculated phase shifts for five of these functions and obtained second virials, bound state energy differences, and total and differential scattering cross sections to compare to the experimental data. We find that none of the previously proposed potentials can represent more than two of the above properties of para-hydrogen. Using the Hartree–Fock dispersion form proposed by Ahlrich et al., but changing the damping constant D from 1.28 to 1.31, a consistent representation is found for all the data except the differential scattering data. To fit the differential scattering data, the collision energy used in the calculation must be 3% larger than the stated value. This difference is within the experimental uncertainty of the differential scattering experiment.