Abundance corrections for spectral lines of neutral atoms, plotted versus the difference between their ionization energy and line excitation potential, E_ion − χ. Three types of abundance corrections are shown: Δ_{3D − ⟨ 3D ⟩}  (left column), Δ _{⟨ 3D ⟩ − 1D} (middle column), and Δ_3D − 1D (right column). Abundance corrections are provided at three different wavelengths: 400 nm (top row), 850 nm (middle row), and 1600 nm (bottom row). The ionization energies of neutral atoms used in plotting this figure are provided in Table 1.