Knowledge Bank

The $\nu 1$ band of HOBr centered at $3614.903cm-1$ has been observed at $0.006cm-1$ resolution. The band is a hybrid type with $|(\partial \mu b/\partial Q1)/(\partial \mu a/\partial Q1)\approx 0.84$. The spectra of both bromine isotopes have been simultaneously fitted with a single calculation which includes all the previously reported rotational transitions. There appear to be no strong local perturbations to complicate the fitting of the line positions. There is a prominent Herman-Wallis effect for the b-type transitions which is well described by linear and quadratic terms in $Ka$. Precise parameters for the upper states and improved parameters for the ground states of both species will be presented as will the Herman-Wallis factor. The rotational constants for the ground state and all three fundamental vibrations will be summarized and the equilibrium structure will be shown.