in the electronic triplet state: current status

Abstract

We review the theoretical work carried out on the tri-hydrogen ion in the electronic triplet state 1 3 E ′, which is split into a and 2 3 A ′ by vibronic interaction. We begin with an overview on analytical potential energy surfaces and calculations of rovibrational states by focusing on our own results, which are based on the most accurate potential energy surfaces available so far. This is followed by an examination of the selection rules and predictions of infrared transition frequencies. Finally, we discuss the Slonczewski resonance states supported by the upper sheet of the potential energy surface. Theoretical work reported here may be of interest for future experiments on the title ion.