Solar IR line profiles at various positions on the disk. First row: 7.3 μm line, second row: 12.2 μm line, and final row: 12.3 μm line. The columns are μ = 1.0, 0.5, and 0.2, in that order. The circles are observations taken from Chang et al. (1991) for the 7.3 μm line and from Brault & Noyes (1983) for the two 12 μm lines. The synthetic spectral lines are calculated for various model atoms using A(Mg ) = 7.6 and employing the ⟨3D⟩ _1D solar model atmosphere. For the synthetic profiles, a macroturbulent velocity of 3.15 km s^-1 and a rotational broadening of vsini = 1.6 km s^-1 are used. For model F, the profile without macroturbulence is also shown (grey full line) to demonstrate its effect.