Comparison of the H₂S and OCS chemical evolution during the final stages of the collapse with different warming curves. Left: H₂S ice and gas-phase abundances during the collapse with the different warming curves. The starting time of the figure has been set to 4×l0⁴ years to show a closer detail of the major changes. The products after 5.5×l0⁴ are very similar in all the models but, in the later stages, the model with a lower final temperature, “Lower T”, shows a drop of the gas-phase H₂S abundance. Center: OCS ice and gas-phase abundances during the collapse with the different warming curves. The starting time of the figure has been set to 4×l0⁴, as in the left panel. The products after 5.5×l0⁴ are very similar in all the models. Right: H₂S/OCS ratio after the collapse with the different warming curves. The models show a ratio close to five except for the model with a lower final temperature.