A study of the electronic structure of α-NaV₂O₅ using angular-resolved soft X-ray spectroscopy

In this dissertation, we use soft x-ray spectroscopy to investigate the electronic structure of the highly anisotropic, strongly correlated transition-metal oxide d.-NaV 2O5. Band structure calculations and theoretical modeling of V-V correlation effects were employed to assist in the interpretation of the experimental data. Our results show that NaV2O5 is a Mott-Hubbard insulator in which the V d-band spanning the Fenni level is split into lower and upper Hubbard bands by strong correlation effects. Resonance inelastic x-ray scattering (RIXS) measurements provide a direct measure of the d-d* excitations between the bands and show that the distance between the centroids of the bands is 1.55 ±.. 0.05 e V.