(a) PtF₄ in C2/m symmetry at 300 GPa. (b) PtF₆ in C2/c symmetry at 300 GPa. (c) Phase stabilities of the considered PtF_x (x = 1–10) compounds with respect to elemental Pt and F₂ solids at 300 GPa. (d) The energy difference between M5d and F 2p orbital at 100 GPa, and the stable F-richest stoichiometry of M (M = Ir, Pt, Au, Hg).