Theoretical study of HfF+ in search of the electron electric dipole moment

We report ab initio relativistic correlation calculations of potential curves for ten low-lying electronic states, the effective electric field on the electron, and hyperfine constants for the 3Δ1 state of a cation of the heavy transition metal fluoride HfF+, which it is suggested can be used in experiments to search for the electric dipole moment of the electron. It is shown that HfF+ has a deeply bound 1Σ+ ground state; its dissociation energy is De=6.4 eV. The 3Δ1 state is obtained as the relatively long-lived first excited state lying about 0.2 eV higher. The calculated effective electric field Eeff=Wd|Ω| acting on an electron in this state is 5.84x1024 Hz/e cm