High resolution spectroscopy of DOBr and molecular properties of hypobromous acid

The ν1 and ν2 bands of DOBr centered near 2668.8 and 852.0cm-1 respectively have been observed at 0.006cm-1 resolution. The ν1 band is perturbed by a quintic anharmonic resonance (ΔKa=0) with 3ν3+ν2. In addition, the millimeter wave spectra arising from the v2=1 and v3=1 states have been observed. All rotational and vibrational spectra from both bromine isotopologs have been fitted with a single calculation. The perturbation in the ν1 band has been well described. Equilibrium rotational and centrifugal distortion constants and changes in quadrupole coupling with the BrO stretch and DOBr bend have been determined. The equilibrium structure has been derived from the DOBr and HOBr rotational constants. The harmonic force field has been calculated and compared with those of related molecules as well as with those derived from ab initio calculations.