Theoretical study of the ArH+ electronic states

Abstract

Potential energy curves, permanent multipole and transition dipole moments were evaluated for the ground and low-lying excited electronic states of the ArH⁺ cation over a wide range of internuclear distance by the multireference averaged quadratic coupled cluster method (MR-AQCC). The electric dipole polarisability of the ground X ¹Σ⁺ state was evaluated by the finite-field method. The permanent multipole moments and dipole polarisabilities corresponding to the ArH⁺ X ¹Σ⁺ state were used to estimate quantum defect functions of the nonpenetrating d- and f-complex Rydberg states of neutral ArH molecule. The ground state dipole function and potential were tested by a simulation of intensity distributions in the rovibrational Δv = 1 bands, radiative lifetimes and rotational g-factors for the X ¹Σ⁺ state.