Resonant dissociative recombination ofH3+

A recently reported peak near 9.5 eV in the cross section for electron impact dissociative recombination of vibrationally cold ${\mathrm{H}}_3^{+}$ is due to four ${\mathrm{H}}_3$ resonance states. Using a complex Kohn, electron scattering variational method to obtain resonance energies and widths and a time-dependent wave packet calculation of the dissociation dynamics in the presence of autoionization, we obtain excellent agreement with the position, shape, and magnitude of the reported feature. Vibrational excitation of ${\mathrm{H}}_3^{+}$ is a dominant competing channel due to a high probability of autoionization during dissociation.