Nonadiabatic corrections to the rotational energies of the hydrogen molecule

Abstract

Nonadiabatic corrections to the rotational energies and rotational constants B ν have been computed by a variational perturbation method for several vibrational levels of the H 2, HD, and D 2 molecules. It is believed that the convergence error in the computed corrections to the energy is less than 10 −3 cm −1. The corrections improve the agreement of theoretical and experimental rotational quanta, but there are still discrepancies that amount in some cases to a few hundredths of a cm −1. These discrepancies are irregular and it is argued that they are at least partly due to experimental inaccuracies.