The permanent electric dipole moments of cobalt monofluoride, CoF, and monohydride, CoH

The optical Stark spectra of the R(4) and Q(4) lines of the [18.8] ³p₄-X³p₄(0,0) band systems of cobalt monofluoride, CoF, and the A′³p₄-X ³p₄(0,0) band systems of cobalt monohydride, CoH, have been recorded using laser induced fluorescence technique. The shifts and splittings caused by the static electric field have been analyzed to give the permanent electric dipole moments, μ_e, of 4.51(5) and 2.82(5) D for the [18.8]³p₄ and X³p₄ states of CoF, and 0.01(8) and 1.88(8) D for the A′³p₄ and X³p₄ states of CoH. The experimental dipole moments are compared with theoretical predictions. A molecular orbital correlation description is used to explain the relative ground state μ_e values for CoH and CoF.