Destruction of H₂S and formation of HS during UV irradiation. Top: data points corresponding to S7 (asterisks), S8 (diamonds), and S9 (triangles) experiments, see Table 1. For each experiment, the integrated absorbance values of the 2550 cm^-1 band of H₂S ice as a function of UV irradiation time, N_s(H₂S), were normalized with respect to their initial values before irradiation, N_s(H₂S)_i. The fits were made using Eq. (10) and rate constant values displayed in the figure. Error bars represent the standard deviation in each experiment. Bottom: normalized integrated absorbance values of the 2483 cm^-1 band attributed to the HS product as a function of UV irradiation time, corresponding to S7 (asterisks), S8 (diamonds), and S9 (triangles), see Table 1. Normalization was done with respect to the integrated absorbance values of the 2483 cm^-1 band after the same irradiation time. The solid line is a fit using Eq. (11) and rate constants displayed in the figure.