Fig. 3. The sticking of O₂ on Cu(111) as a function of θ/θ_max at 216 meV (a) and 379 meV (b) normal incidence energy for T_surf = 90 K (red), 300 K (blue), 400 K (yellow), 500 K (green), 670 K (black). S(θ) as a function of θ/θ_max at 379 meV (normal incidence) for 90 K < T_surf <670 K.