Time-dependent evolution of the fractional abundances of several important species (CO, CO₂, H₂O, CH₃ OH, CH₄, NH₃, HC₃N, N₂H⁺, and HCO⁺) with respect to H₂ using the TMC1 model calculated by the Nautilus code. The letter J represents those species on the grains. The black solid lines are the results adopting the reaction network from Wang et al. (2021), and the red crosses represent the results adopting the reaction network from Ruaud et al. (2016), as an example network in the Nautilus package.