4 considered to be equivalent metals are actually differ- ent. We believe this finding may apply to many other strongly correlated systems presenting metal-insulator transitions, with pressure opening inequivalent pathways through their phase diagrams. We thank E. Tosatti for stimulating discussions and ac- knowledge a BQR of the Universit´ e Paris-Sud, the “Tri- angle de la Physique”, the Austrian Science Fund (FWF, science college W004), and the EU research network RP7 MONAMI for financial support. 5470 5468 5466 5464 (x) (T) (P) GLYPH<s40>GLYPH<s97>GLYPH<s41>  PI  PM (P) Photon Energy (eV) Binding Energy (eV) -2 0 GLYPH<s40>GLYPH<s99>GLYPH<s41> (T) (x) 400 300 200 100 T (K) 0.02 0.01 0.00 +Cr (V$_{1-x}$M$_{x}$)$_{2}$O$_{3}$ PM PI AFI 10 14 6 2 P (kbar) -2 0 GLYPH<s40>GLYPH<s100>GLYPH<s41> 5470 5468 5466 5464 GLYPH<s40>GLYPH<s98>GLYPH<s41> Intensity (arb. units) FIG. 3: (Color online) (a) V-K XAS spectra for powder sam- ples of (V 1$_{−}$ x Cr x ) 2 O 3 as a function of pressure ( × ) [ x = 0 . 028; 5 and 7 kbar (lower curves); 5 and 11 kbar (upper curves)] (P), temperature ( △ ) [ x = 0 . 011; 200,300 K] (T), and dop- ing ( ◦ ) [ x = 0, 0.011] ( x ) (cf. points in the phase diagram; the pressure scale refers to the x = 0 . 028 doping). The spec- tral differences PM − PI ( × 3) shown for the three datasets (b) demonstrate the nonequivalence between P and temperature- doping. The x - T equivalence is confirmed by the photoemis- sion spectra ( hν = 9 eV) (c) and their spectral differences (d) (from Ref. [15]). Our finding clearly shows the limits of the common as- sumption that temperature/doping- and pressure-driven MIT in V$_{2}$O$_{3}$ can be equivalently described within the same phase diagram [25],[27]. Indeed, the two different PM electronic structures that we observed reflect differ- ent mechanisms driving the MIT along different path- ways. In the doping-driven MIT, the metallic phase is characterized by an increased occupation of the a$_{1}$$_{g}$ electrons indicating a reduced “effective crystal-field- splitting” as the main driving mechanism towards metal- licity [8, 9], related to the jump of the lattice parameter c/a (1.4%) at the MIT [25]. 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