A new determination of the ground state interatomic potential for He2

Abstract

A simple accurate potential of the HFD-B form, which appears to be the best characterization of the He-He interaction constructed to date, is presented. It has been fitted to low temperature second virial coefficient data and recent accurate room temperature viscosity data, while at the same time pinning the repulsive wall to the value calculated by Ceperley and Partridge at 1 Bohr. It possesses a well depth of 10·948 K, considerably deeper than many of the recent empirical or ab initio potentials. It reproduces, within experimental error, such dilute gas properties as second virial coefficients, viscosities and thermal conductivities over a wide temperature range. It also predicts, within experimental error, such microscopic properties as differential cross sections, high energy integral cross sections and backward glory oscillations in the integral cross sections. Finally, it accounts for nuclear magnetic relaxation in ³He and supports a weakly bound state in the ⁴He interaction.