High-field level-crossing and Stark studies of the A 2Σ+ state of OD

We have carried out a high‐field level‐crossing experiment on the $\text{ν = 0, N=1, J=3/2}$ ot the OD A ²Σ⁺ state. A precise measurement of the magnetic fields at which three crossovers are observed permits a determination of the three hyperfine constants b = 110.4 ± 2.6 MHz, c = 22 ± 14 MHz, and eQq = 0.09 ± 0.05 MHz (3σ). In addition, we have applied a static electric field parallel to the magnetic field and observed a shift in the location of the high‐field level crossings from which we calculate the dipole moment of this excited state to be 1.72 ± 0.10 D (3σ). A comparison of these structural parameters is made with ab initio calculations.