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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}$$_{g}$ electrons indicating a reduced “effective crystal-field- splitting” as the main driving mechanism towards metal- licity [8, 9], related to the jump of the lattice parameter c/a (1.4%) at the MIT [25]. In contrast, when pressure is applied the a$_{1}$$_{g}$ occupation remains basically unchanged, so that this metallic phase seems to originate rather from an increased bandwidth, without any relevant changes of the orbital splitting. The smaller c/a jump observed un- der pressure (0.7 %) corroborates our analysis. 

In conclusion, doping, temperature and pressure are shown to act differently on the interplay between electron correlations and crystal field, so that states previously 

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. 

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