  Using the ground potential energy surface[M. Ayouz \textit{et\, al}. J. Chem
Phys \textbf{132} 194309 (2010)] of the H$_3^-$ molecule, we have determined
the energies and widths of the complex resonant levels of H$_3^-$ located up to
4000 cm$^{-1}$ above the dissociation limit H$^-$+H$_2(v_d=0,j_d=0)$. Bound and
resonant levels of the H$_2$D$^-$ and D$_2$H$^-$ isotopologues have been also
characterized within the same energy range. The method combines the
hyperspherical adiabatic approach, slow variable discretization method, and
complex absorbing potential. These results represent the first step for
modeling the dynamics of the associated diatom-negative ion collision at low
energy involving rotational quenching of the diatom and reactive nucleus
exchange via weak tunneling effect through the potential barrier of the
potential energy surface.
