Jonathan Tennyson,

Department of Physics & Astronomy, University College London, London WC1E 6BT, UK

The experiments of Carrington and co-workers on the photodissociation spectrum of H_{3}^{+} have presented a considerable challenge to theory over a number of years. (Semi-)classical studies have answered some questions concerning these spectra, in particular the observed dissociation branching ratios of the mixed isotopomers is now well understood. However many aspects of the spectrum have so far defied proper analysis.

Up until recently quantum mechanical studies have been hampered both by the computational demands of such calculations and the lack of a reliable potential energy surface. The UCL group has constructed two new potential using respectively available spectroscopic data and new ab initio electronic structure calculations. These potentials represent correctly the dissociation pathways of the system. Progress in performing rotation-vibration calculations, using massively parallel computers and the new potentials, will be reported at the meeting.