Dust density setup in the model of the large dust population (left) and small dust population (right). The colored contours follow the dust temperature at which the considered molecules freeze out according to their desorption temperature given in Table 2. The dotted black lines denote a visual extinction (A_v) of 0.1, 1, and 10 mag as measured from the stellar position. The onset of ice formation is set to A_v < 1.5 mag in the fiducial model.