Jahn-Teller Effect in Three-Body Recombination of Hydrogen Atoms

The three-body recombination rate coefficients of the H+H+H$\to$H$_2$+H process for different final rovibrational levels of H$_2$ are determined using a fully-quantum mechanical approach at zero total angular momentum. The Jahn-Teller coupling between the lowest electronic states of the H$_3$ system is accounted for. It is found that the Jahn-Teller effect substantially enhances the recombination rates for deeply bound dimers at room temperature, but only leads to a 12\% increase of the total three-body recombination rate. It is also found that the nascent population of the H$_2$ molecules, formed in the recombination process, is dominated by highly excited rovibrational levels, which should have a substantial impact on astrophysical models of environments where atomic hydrogen is present.