Gross thermodynamics of two-component core convection

  title={Gross thermodynamics of two-component core convection},
  author={D. Gubbins and D. Alf{\'e} and G. Masters and G. D. Price and M. Gillan},
  journal={Geophysical Journal International},
We model the inner core by an alloy of iron and 8 per cent sulphur or silicon and the outer core by the same mix with an additional 8 per cent oxygen. This composition matches the densities of seismic model, Preliminary Reference Earth Model (PR-EM). When the liquid core freezes S and Si remain with the Fe to form the solid and excess 0 is ejected into the liquid. Properties of Fe, diffusion constants for S, Si, 0 and chemical potentials are calculated by first-principles methods under the… Expand

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