Knowledge Bank

The rotational spectra of IO in vibrational states up to $v=13$ in the $X12\Pi 3/2$ state and up to $v=9$ in the $X22\Pi 1/2$ state have been observed in an $O2$ discharge over molecular $I2$. In addition, $I18O$ has been observed for both the $X1$ and $X2$ states up to $v=5$. All data have been analyzed simultaneously with fixed isotopic ratios among the constants. This extends the data set for the $X1$ state described last year at this meeting and provides the first high resolution data for the $X2$ state and for $I18O$. An extensive set of parameters has been derived. These will be interpreted in terms of the electronic structure and the interatomic potential.