The synthetic spectra for the H12 (blue) and W07 (red) models at a spectral resolution R = 1500. Because the W07 models are optically-thick in many highly-excited levels, the strongest H₂O lines peak in the mid-IR rather than the far-IR. The H12 model predicts some rovibrational emission at 6 μm because of the high temperature, with a strength that could further constrain the temperature and density of the highly excited H₂O.