Beyond universality: parametrizing ultracold complex-mediated reactions using statistical assumptions

Abstract

We have calculated accurate quantum reactive and elastic cross-sections for the prototypical barrierless reaction D${}^{+}$ + H${}_2$($v$=0, $j$=0) using the hyperspherical scattering method. The considered kinetic energy ranges from the ultracold to the Langevin regimes. The availability of accurate results for this system allows to test the quantum theory by Jachymski et al. [Phys. Rev. Lett. 110, 213202 (2013)] in a nonuniversal case. The short range reaction probability is rationalized using statistical model assumptions and related to a statistical factor. This provides a means to estimate one of the parameters that characterizes ultracold processes from first principles. Possible limitations of the statistical model are considered.

References in corpus (9)

• Observation of Quantum Effects in sub Kelvin Cold Reactions
• Feshbach resonances in ultracold atomic and molecular collisions: threshold behaviour and suppression of poles in scattering lengths
• Inelastic collisions of ultra-cold heteronuclear molecules in an optical trap
• Strong dependence of ultracold chemical rates on electric dipole moments
• Dynamics of gas phase Ne${}^{\ast }$ + NH${}_3$ and Ne${}^{\ast }$ + ND${}_3$ Penning ionization at low temperatures
• Quantum Langevin model for exoergic ion-molecule reactions and inelastic processes
• Statistical product distributions for ultracold reactions in external fields
• Quantum defect model of a reactive collision at finite temperature
• Ultracold mixtures of metastable He and Rb: scattering lengths from ab initio calculations and thermalization measurements