Communication: electric dipole moment and hyperfine interaction of tungsten monocarbide, WC

The [17.6]2← X(3)Δ(1)(1,0) band of tungsten monocarbide, WC, was recorded using laser induced fluorescence both field-free and in the presence of a static electric field. The Stark induced shifts of the R(1) and Q(2) lines were analyzed to produce values for the permanent electric dipole moments, μ, of 3.90 ± 0.04 D and 2.57 ± 0.04 D for the X(3)Δ(1)(v = 0) and [17.6]2(v = 1) states, respectively. An upper limit to the Ω-doubling parameter, õ(Δ), of 2 MHz is established. The (183)W(I = 1/2) Fermi contact parameter, b(F), for the X(3)Δ(1)(v = 0) is estimated to be 1363 MHz. The results are compared with theoretical predictions and a molecular orbital correlation description.