Comparison between the chemical models presented in Furuya et al. (2016) (top panels) and the model utilized here (bottom panels). The 1D RHD simulations of a protostellar collapse are from Masunaga & Inutsuka (2000). The solid lines indicate the ice mantle, the dashed lines present the ice surface, and the dotted lines show the gas-phase ratios in the three-phase models. The log-scale on the x-axis is reversed on the second row.