Rotation-vibration states of H3+ at dissociation

Calculations are presented which estimate energies for all the bound rotation-vibration energy levels of H-3(+) with rotation angular momentum J=0, 2 and 8. The calculations, which use Radau coordinates with z-axis of the molecule embedded perpendicular to the molecular plane, are performed on 128 nodes of a massively parallel computer. It is found that convergence with respect to basis set size of the higher J states is fairly slow and that further improvements are beyond the capabilities of the current computational set-up. (C) 2003 American Institute of Physics.