H₂S on the surface after deposition at 8 K (top left) and during TPD at 50 K (top middle), at 100 K, (top right), at 200 K (bottom left) and 300 K (bottom middle). The bottom right panel also shows the surface at 300 K but with the chains being highlighted by using one color per chain. In these simulations, the molecules in the ice do not shield each other and photons can therefore dissociate molecules from the top layers to the bottom layers. The deposition rate of H₂S is 1 ML s⁻¹, the heating ramp is 1 K min⁻¹ and G₀ = 5 × 10⁶.