Abstract
Effective (mass-dependent) potential energy curves of the A(2)Sigma(+) electronic states of the (OH)-O-16 and (OD)-O-16 isotopomers of the hydroxyl radical OH are constructed by morphing reliable ab initio potential energy curves within the framework of the Jenc reduced potential energy curve (RPC) approach. In turn, the resulting potential energy curves are used to determine the radial functions describing the spin-rotation and hyperfine energy patterns of the spin-rovibrational energy levels by morphing/fitting their ab initio/empirical approximants.
The resulting functions allow for reliable predictions for untested spectral regions, provide a base for testing the impacts of external fields on the measured spectral transitions, and allow for accurate estimations of the mass sensitivity of the hydroxyl spectral transitions appearing as suitable probes of a cosmological variability of the electron-to-proton mass ratio. (C) 2021 Elsevier Ltd. All rights reserved.