Species densities for the PV models for the six SNe Ia in our sample. These species densities are calculated as the product of the abundance and density profiles and can be used to compare models with different density profiles. The faint red and faint blue profiles correspond to the HESMA delayed-detonation (Seitenzahl et al. 2013) and double-detonation (Gronow et al. 2021) models, respectively. The colours of the PV model profiles correspond to the colours in Fig. 1.