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Table 1

Condensation temperatures and volume mixing ratios of the chemical species.

Species (Y) Tcond [K] vY, no C vY, w C
CO 20 0.45 × C/H 0.45 × C/H
CH4 30 0.45 × C/H 0.25 × C/H
       
CO2 70 0.1 × C/H 0.1 × C/H
       
H2O 170 O/H - (3 × MgSiO3/H + 4 × Mg2SiO4/H + CO/H
       
+ 2 × CO2/H + 3 × Fe2O3/H + 4 × Fe3O4/H) see vY, no C
       
Fe3O4 371 (1/6) × (Fe/H - S/H) (1/6) × (Fe/H - S/H)
       
C (carbon grains) 626 0 0.2 × C/H
FeS 704 S/H S/H
Mg2SiO4 1354 Mg/H - Si/H Mg/H - Si/H
       
Fe2O3 1357 0.25 × (Fe/H - S/H) 0.25 × (Fe/H - S/H)
       
MgSiO3 1500 Mg/H - 2 × (Mg/H - Si/H) Mg/H - 2 × (Mg/H - Si/H)

Notes. Condensation temperatures for molecules are taken from Lodders (2003). For Fe2 O3 the condensation temperature for pure iron is adopted (Lodders 2003). Volume mixing ratios vY (i.e. by number) are adopted for the species as a function of disc elemental abundances (see e.g. Madhusudhan et al. 2014). We note that the Mgabundance is always larger than the Si abundance. We follow here the different mixing ratios from Bitsch & Battistini (2020).

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