Example of the radiative energy exchange rate Q versus geometrical height z for the M2V star. Top panel: the Q rate computed using the ODF from SYNSPEC data (black solid line) and the ODF from ATLAS (red solid line). The logarithm of the Rosseland optical depth is shown in the top axis. The area of the difference is shaded in grey. The zero of the geometrical height z is at the continuum optical depth at 500 nm τ₅ = 1. The range of heights of the cooling (Q < 0) and heating (Q > 0) components are indicated in cyan and orange respectively. The heights z_b, z_c→h, and z_t are used as integral bounds to calculate the deviation measures χ_C and χ_Η (Eqs. (13) and (14)). The height z_c→h is also marked with a vertical black line. Bottom panel: absolute difference between the Q values.