Modelled volume of stishovite to post-stishovite as a function of pressure and temperature. Data points are from the published literature (Ito et al. 1974; Andrault et al. 2003; Fischer et al. 2018; Zhang et al. 2021). The pressures of the data from Andrault et al. (2003) and Zhang et al. (2021) are adjusted as described in Section 5.3. Data from Fischer et al. (2018) was not used in the inversion, but is shown for comparison with the model.