Trends in the band structures of the group-I and -II oxides.

Measured and calculated band structures for the six lightest group-I and -II oxides are reported. Band structures have been measured using electron momentum spectroscopy, a technique that maps the ground-state occupied orbitals resolved both in energy and momentum. Measurements are compared with first-principles calculations carried out within the linear combination of atomic orbitals approximation using both Hartree-Fock (HF) and density functional (DFT) methods.