Spectroscopy and metastability of the HSS− anion§

Abstract

Accurate ab initio calculations on the potential energy surfaces (PESs) of the lowest electronic states of the neutral HSS and those of the electronic states of the HSS− negative ion correlating to the bound asymptotes of this molecular system, reveal that the ground state of HSS− (i.e. 1A′) and the long range parts of the anionic PESs are stable against the autodetachment processes. In light of these calculations, the [HS + S]− and [S2 + H]− reactive systems are examinated and found forming the HSS− ( 1A′) ions either directly or after spin–orbit and/or vibronic and/or Renner–Teller couplings, in competition with fast electron loss processes. The three-dimensional PES of the unique bound electronic state of HSS− (i.e. 1A′) is generated using the coupled cluster approach and a large basis set. A set of spectroscopic parameters for HSS−/DSS− ( 1A′) and their vibrational spectra up to 3700 cm−1 are deduced from the 3D PES. §Dedicated to Professor Pavel Rosmus on his retirement.