Ab initio spectroscopy of D₂H⁺ near dissociation

Abstract

Extensive calculations for the vibrational band origins of D₂H⁺ up to dissociation are presented. Due to the high density of vibrational states near dissociation, huge basis sets needed to be used as well as massively parallel computers. We have found 1209 A₁ and 1078 B₁ bound states, some of which display long-range features, which are analysed in detail. The calculations were performed within the Born–Oppenheimer approximation and non-adiabatic corrections to it are evaluated. However, the main source of error for the states near dissociation arises from the Potential Energy Surface at high energies.

Keywords:

• Ab initio spectroscopy
• D2H+
• Vibrational states

Acknowledgement

This work was performed as part of EPSRC's ChemReact computing consortium.