ON THE STABILITY OF THE AUTODISSOCIATIVE GROUND ELECTRONIC-STATE OF BEH2+

It is shown that the mechanism of spontaneous infrared emission enhanc es substantially the stability of the long-lived ground electronic sta te of the exotic BeH2+, whose autodissociation becomes possible only v ia tunneling. The system, initially situated in any vibrational level (except the high-lying ones for which dissociation is predominate) and statistically distributed over all rotational states, reaches stabili ty through a cascade of dipole emissions toward lower levels. The rapi d spatial variation of the dipole moment results in fast radiative pro cesses and might suggest experimental observations easier to perform. The methodology is based on a recently presented analytic discrete var iable representation (DVR) [D. T. Colbert and W. H. Miller, J. Chem. P hys. 96, 1982 (1992)] that facilitates calculations. This might prove particularly useful to spectroscopists, allowing a check of the qualit y of potentials produced by inversion methods or the reliable calculat ion of spectrochemical quantities. (C) 1995 John Wiley and Sons, Inc.