Electronic Structure with Rovibrational Calculations of the Magnesium Monohalides MgX and Their Cations MgX(+) (X = Cl, Br, and I)

[Image: see text] Alkaline-earth monohalides are popular compounds that are used in various applications. Little is known, however, in terms of electronic structure, about their cations and their low-lying electronic states. We present in this work electronic structure ab-initio calculations based on multireference configuration interaction plus Davidson correction of three magnesium monohalides and their cations (MgCl, MgBr, MgI, MgCl(+), MgBr(+), and MgI(+)). We determine the spectroscopic constants T(e), R(e), ω(e), B(e), and α(e) and the dissociation energies D(e) for their bound states. Additionally, we investigate their vibrational properties by calculating the vibrational eigenvalue E(v), the rotational constant B(v), and the centrifugal distortion constant D(v). We additionally study the electric charge distribution of several states by determining their permanent dipole moment and transition dipole moment curves. Finally, we calculate the Franck–Condon factors and the radiative lifetimes as precursors for laser cooling experiments.