The Forces Between Hydrogen Molecules

Abstract

Earlier calculations of the ${\mathrm{H}}_2$-${\mathrm{H}}_2$ interaction, based on the use of screening-constant functions, seemed to lead to reasonable answers only with the use of a nuclear charge much greater than the correct value for the isolated molecule, $Z_0=1.166\mathrm{}$. The present work is a recalculation of the exchange forces for $Z=Z_0$. A small numerical error in the earlier work is eliminated, and the exchange energy, instead of being slightly negative as reported previously, is actually positive. This removes all perplexing features from the problem and yields results in substantial agreement with experiments.