Water and hydroxyl emission in PJ183+05. Left: Scheme of the J ≤ 4 energy levels of the H₂O molecule, and for the Ω = 1/2 and 3/2 levels of the OH molecule. Solid lines mark the transitions detected in our study, dashed lines show the transitions that we observed but not detected. The channels of IR pumping relevant for this study are also marked with dotted arrows. Right: Comparison between the luminosity of H₂O and OH transitions, normalized to the dust IR luminosity, in PJ183+05 and in other z > 6 quasars from Pensabene et al. (2021, 2022). All of the water and hydroxyl transitions detected in our work show line-to-IR luminosities that are ∼3× higher than the values observed in other quasars at the same redshift.