Fig. 1. A schematic illustrating how ARROWS³ guides precursor selection.

a Reactions based on different precursor sets (R1, R2, and R3) are initially ranked by their driving force ($△\mathrm{G}$) to form the target, which is obtained from density functional theory (DFT) calculations. b Experiments are performed at iteratively higher temperatures to identify reaction intermediates. The chemical formulae listed in this panel represent the phases identified from X-ray diffraction (XRD) measurements. c Pairwise reaction temperatures (T_rxn) and products are gleaned from the experimental data. d Using the identified pairwise reactions, intermediates are predicted for other precursor sets and their remaining driving forces ($△{\mathrm{G}}^{\prime }$) are updated accordingly. e The precursor ranking is updated based on the newly calculated $△{\mathrm{G}}^{\prime }$. All chemical formulae shown are placeholders for arbitrary compounds, and in general there is no restriction on the compositions where ARROWS³ is applicable.