Results for , TATA⁺, Eosin Y and Rhodamine B photosensitizers (radiative properties are in Fig 2) for the incident solar spectrum in Fig 3, at selected optical thicknesses and (see Eqs 4–7 and Table 1): Reference absorptance , reference MVRPA (slab thickness <i>L</i> = 1 <i>cm</i>; incident flux density <i>q</i>₀ = 1743 <i>μ</i>mol_<i>hν</i>.m⁻².s⁻¹ and 1721 <i>μ</i>mol_<i>hν</i>.m⁻².s⁻¹ for TATA⁺), relative difference Δ(<i>X</i>) between these values and those obtained with a model denoted <i>X</i> (see Eq 29).

X ≡ (Φ = 0) when luminescence is neglected, X ≡ (j = 0) for zero-order scattering expansion () as presented in Section 4.1, X ≡ (j ≤ 1) for first-order scattering expansion () as presented in Section 4.3, X ≡ (elastic) and X ≡ (gray) for elastic and gray models presented in Section 3.3, and for elastic and gray P1 approximations presented in Section 4.2 and finally, for the gray single-scattering approximation presented in Section 4.3. Results for do not include all X models, since zero-order expansion already provides a reference solution. The relative uncertainty of the Monte Carlo absorptance estimation is always lower than 1%; the precision indicated accounts for case-by-case absolute uncertainty.