Fig. 2. Metal/silicate N partition coefficients (D_N^{metal/silicate}) as a function of oxygen fugacity.

All $D_N^{\mathrm{metal}/\mathrm{silicate}}$ data were obtained under largely variable conditions (P = 0.85–26 GPa; T = 1523–3400 K; NBO/T = 0.02–3.1; and fO₂ = IW–0.1 to IW–5.5) and were taken from K2011, 2013, 2015 (refs. ^64,92,93), R2013 (ref. ⁹⁴), L2016 (ref. ³⁵), D2017 (ref. ⁹⁵), G2019a (ref. ⁴⁰), G2019b (ref. ¹⁸), S2019 (ref. ⁴¹), D2019 (ref. ³⁶), G2021 (ref. ⁴²), and J2021 (ref. ⁴³). The $D_N^{\mathrm{metal}/\mathrm{silicate}}$ are dominantly controlled by fO₂, and the scatter of $D_N^{\mathrm{metal}/\mathrm{silicate}}$ at a given fO₂ is caused by the variation of other parameters, such as P–T and the compositions of metallic and silicate melts as summarized in Eq. (1). Note that all literature fO₂ values were recalculated by using the approach described in Methods. Source data are provided in Supplementary Data 2.