Theoretical study on ThF⁺, a prospective system in search of time-reversal violation

The low-lying electronic states of ThF⁺, a possible candidate in the search for - and -violation, have been studied using high-level correlated relativistic ab initio multi-reference coupled-cluster and configuration interaction approaches. For the state component with Ω = 1 (electron electric dipole moment 'science state') we obtain an effective electric field of , a - and -odd electron-nucleon interaction constant of kHz, a magnetic hyperfine interaction constant of MHz for ²²⁹Th (), and a very large molecular dipole moment of 4.03 D. The Ω = 1 state is found to be more than 300 cm^-1 lower in energy than (), challenging the state assignment from an earlier theoretical study on this species (Barker et al 2012 J. Chem. Phys. 136 104305).