The molecular frame electric dipole moment and hyperfine interactions in hafnium fluoride, HfF

The (1,0) [17.9]2.5-X-2 Delta(3/2) band of hafnium monofluoride (HfF) has been recorded using high-resolution laser-induced fluorescence spectroscopy both field-free and in the presence of a static electric field. The field-free spectra of (HfF)-Hf-177, (HfF)-Hf-179, and (HfF)-Hf-180 were modeled to generate a set of fine and hyperfine parameter for the X-2 Delta(3/2)(v = 0) and [17.9]2.5 (v = 1) states. The observed optical Stark shifts for the (HfF)-Hf-180 isotopologue were analyzed to produce the molecular frame electric dipole moments of 1.66(1) D and 0.419(7) D for the X-2 Delta(3/2) and [17.9]2.5 state, respectively. Both the generalized effective core potential and all-electron four component approaches were used in ab initio calculations to predict the properties of ground state HfF including equilibrium distance, dipole moments, quadrupole coupling, and magnetic hyperfine constants. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4794049]