Radial profiles of various properties during the collapse of a 1  M_⊙ dense clump at a core central density ρ_c = 6 × 10^-2  g   cm^-3, for the grey models (black dashed lines) and multigroup models (coloured lines). For the multigroup run, the gas and total radiative quantities (summed over all groups) are plotted in magenta, while the other colours represent the individual groups (the colour-coding is the same as in Fig. 5); see legend in (b). From top left to bottom right: (a) density, (b) gas temperature (magenta and black) and radiation temperature (other colours), (c) velocity, (d) entropy, (e) optical depth, (f) luminosity, (g) Rosseland average opacity, and (h) radiative flux.