Valence-band electronic structure of V2 O3: Identification of v and O bands

We present a comprehensive study of the photon energy dependence of the valence band photoemission yield in the prototype Mott-Hubbard oxide V2 O3. The analysis of our experimental results, covering an extended photon energy range (20-6000 eV) and combined with GW calculations, allows us to identify the nature of the orbitals contributing to the total spectral weight at different binding energies, and in particular to locate the V4s states at about 8 eV binding energy. From this comparative analysis, we conclude that the intensity of the quasiparticle photoemission peak, observed close to the Fermi level in the paramagnetic metallic phase upon increasing photon energy, does not have a significant correlation with the intensity variation in the O2p and V3d yield, thus, confirming that bulk sensitivity is an essential requirement for the detection of this coherent low-energy excitation.