OH spectrum and nearby transitions of TiO₂, HCN and SO₂ observed in the range 265.65 to 266.05 GHz toward omi Cet (Mira). The frequencies of the two hyperfine transitions of OH in the υ = 0, J = 35/2 rotational level are indicated with two light green vertical lines. The F' – F'' = 17 – 17 hyperfine transition of the J = 35/2 level is blended with the 24(2, 22) – 24(1, 23) transition of TiO₂. This spectrum is extracted from a 0.″2×0.″2 region containing all the OH emission.