Knowledge Bank

A sufficient concentration of NO$3$ trapped in solid neon has been produced for detection of all of its previously reported infrared bands between 700 and 2600 $\backslash wn$, most of which lie within 2.5 $\backslash wn$ of the gas-phase band origins. Analysis of the infrared spectra obtained for isotopologues of NO$3$ which contain nitrogen-15 and/or oxygen-18 is consistent with a planar, threefold symmetric structure for the ground-state molecule and provides information supporting the occurrence of extensive mixing of ground-state vibrational levels of $E\prime$ symmetry and vibronic interaction with the {$B~$} $2$E excited electronic state.