  A very recently method for classical trajectory calculations for three-body
collision [J. P\'{e}rez-R\'{i}os, S. Ragole, J. Wang and C. H. Greene, J. Chem.
Phys. {\bf 140}, 044307 (2014)] has been applied to describe
ion-neutral-neutral ternary processes for low energy collisions: 0.1 mK - 10
mK. As a result, a threshold law for the three-body recombination cross section
is obtained and corroborated both, experimentally and numerically. The derived
threshold law predicts the formation of weakly bound dimers, with binding
energies comparable to the collision energy of the collisional partners. In
this low energy range, this analysis predicts that molecular ions should
dominate over molecular neutrals as the most products formed.
