Resonant ion-pair formation in electron collisions with rovibrationally cold ${\mathrm{H}}_3^{+}$

Experimental and theoretical cross sections for the resonant ion-pair formation (RIP) in electron collisions with rovibrationally cold ${\mathrm{H}}_3^{+}$ ions are presented. Absolute cross sections for the RIP process producing ${\mathrm{H}}^{-}$ ions are measured for center-of-mass energies between 2–20 eV using the CRYRING, heavy-ion storage ring. Theoretical cross sections are obtained using wave-packet propagation on both one- and two-dimensional models of relevant diabatic-potential energy surfaces and couplings of ${\mathrm{H}}_3^{+}$ and ${\mathrm{H}}_3.$