Reorientation cross sections for molecular hydrogen

Abstract
Previous expressions for reorientation cross sections based on the assumption of a pure‐P2 potential are extended to include the second dominant intermolecular term, that of the quadrupole‐quadrupole interaction. One particular result is that the semiempirical method of analysis previously developed is essentially unaffected by the inclusion of the quadrupole‐quadrupole interaction. Explicit expressions are given which show how the cross section depends upon the two above‐mentioned interactions.