The hyperfine interaction in the A Π 12 2 and X +2 states of ytterbium monofluoride

The fine and hyperfine interaction parameters in the A Π 12 2 (v=0) and X +2 (v=0) states of the odd metal nuclear spin isotopologues of ytterbium monofluoride, Yb171 F and Yb173 F, have been determined from an analysis of high-resolution laser induced fluorescence spectra of the A Π 12 2 X +2 (0,0) band. The observed ground X +2 (v=0) state Yb171 (I=12) Fermi contact parameter is significantly smaller than that determined from the matrix isolation electron spin resonance measurement [Van Zee, J. Phys. Chem. 82, 1192 (1978)]. An interpretation of the Yb 173,171 magnetic hyperfine and nuclear electric quadrupole coupling parameters is given.