Abundances of 11 COMs with respect to H₂ for models N2-CR50 (a), N3-CR50 (b), N4-CR50 (c), and N5-CR50 (d). In each panel the different symbols indicate the abundances calculated at T = 150 K for different minimum dust temperatures. In each panel the horizontal black lines show the observed abundances relative to H₂ (Table E.3). The gray boxes show the 1σ uncertainties. The arrow indicates an upper limit. In panel a the chemical abundances lower than 4 × 10⁻¹⁴ are not visible.