Theoretical calculation of rovibronic energy levels and anharmonic resonances in the ground X 2Π state of HCP+ and DCP+

Abstract

The spin–rovibronic levels of the HCP⁺ radical cation and its deuteriated isotopomer in the ground X ²Π state have been studied using high-level ab initio methods followed by variational calculations on the computed potential energy surfaces. All experimental levels are reproduced within 8 cm⁻¹ and predictions of the rovibronic levels (K ≤ 3) for energies up to 4500 cm⁻¹ for HCP⁺ and 4000 cm⁻¹ for DCP⁺ are provided. Anharmonic resonances are analyzed in detail and found to be more complex than previously thought.