Metallicity as a function of mass and phase diagrams. Left: metallicity as a function of gas mass. The grey lines represent the profiles computed for single objects in our sample, whereas the coloured dots are the values computed at R_500, c (again, for each group and cluster present in our sample). The colour-coding is given by the virial mass (M_vir) of the systems. Centre and right: density–temperature phase diagram for the less massive system (centre; M_vir = 10¹³ h⁻¹ M_⊙) and the most massive one in our sample (right; M_vir = 9.8 × 10¹⁴ h⁻¹ M_⊙). The colour-coding is given by the mass-weighted metallicity in each density–temperature bin. The dashed horizontal black lines represent the 0.1 keV (1.16 × 10⁶ K) temperature cut, adopted to separate ‘hot’ and ‘cold’ gas phases. The dashed vertical line marks the gas density at R_500, c. To the right of this line are the particles inside R_500,c, and to the left the particles located at larger radii.