Best fits of the solar flux spectrum of Kurucz (2005; black dots) with different sets of 3D NLTE CO⁵BOLD spectra (red dashed line), adopting the same continuum level as in Fig. C.1. From top to bottom: Cases IIa, IIb, and IIc are all based on line list G09, but assume different chemical abundances and rest wavelengths of the blend lines (see text and Table C.1 for details). The right y-axis defines the scale of the residuals (thin blue line).